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I C Digital 

Frequency Counter 



FEBRUARY 1968 
An inflated 6(k 



AMATEUR RADIO 



Amateur I C's 



Ferris Wheel Antenna 



Thin Line Generator 



High Quality Hybrid 
Receiver 



Hydronics or Radio? 
Ham Club Publicity 



How's Your Club Paper? 



Electronic Temperature 
Measurements 



The Quartenna Dummy 
Load 




* 






LV 




K 





VI 




&5 

n it 



iw 





And many more in this 
Issue 



CT 




1 



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An Integrated Circuit Electronic Counter 

A useful piece of ham gear 



W!PLJ„„ 6 



January 1968 

Vol. XLVil No. I 

Kayla Bloom WIEMV 
Editor 



Published by 

Wayne Green, W2NSD/I 



How Come? „ 

A good questFon 



An Amateur Tries IC's .___ _____ 

The uses of integrated circuits 



W4YM_ „.„ 14 



„VE3DAN. M _ 16 



100 KHZ Thin-Line Pulse Generator W2DXH 

Frequency Standard with (Cs 

The Nurture and Care of a Junk Box „„ „_„„.™W0HMK. 

Selective collecting 

How to Plan Your Own DXpedition „. .V/4PJG. 

DXIng in style and comfort 

How is Your Club Paper — Good or Bad? K6GKX. 

Make the readers notice 



24 



_ 30 



34 



38 



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No extra charge for second color 
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advertising to hams, get our fuH 
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from Wayne Green W2NSD. 



over 



Photograph of static electricity 
as recorded on file. KlGUU. 



High Quality Hybrid Receiver _ VEITG/VEIADH 

Restoring the lost art of home-brew 



42 



Tips for the CW Contester and DX'er w 

From one of the great CW contesters 



KH6IJ 50 



How to Publicize Your Club 

Getting activities into print 

Technical Aid Group ..... 

Where to look for help 



.„„„ K4HKD 



■ ■■-#■ ■*■+■¥■-+ -m i 



The Quartenna 

How to shrink a Cantenna 



54 



58 



™ WA6QBH 64 



Hydronics or Radio? .„„., 

Underwater propagation 



VE7BS 



66 



73 Magazine is published monthly 
by 73, Inc, Peterborough, N.H. 
03458. The phone is 603-924-3873, 
Subscription rate: S5.00 per year, 
$9.00 for two years, $12.00 for three 
years. Second class postage is paid 
at Peterborough, New Hampshire, 
and at additional mailing offices. 
Printed in Pontiac, Illinois, U.S.A. 
Entire contents copyright 1967 by 
73, Inc. Postmasters, please send 
form 3579 to 73 Magazine, Peter- 
borough, New Hampshire 03458. 



Electronic Temperature Measurements _ K6EAW. 

Determining temperature rise in components 



70 



Da W2N5D/I 
Propagation 



Editorial Tberties 

tullwl tfcli w I u u J ■ I V<J ...... minium 



Letters 



Caveat Emptor „. 



■ ■ ■ ■ ' *TM fi ■ mm i 



72 

■-■p hitii im t in ■ i ■ w ■■ ■ 9 •mm 



86 

mm * ■ 



FEBRUARY 1968 



I 




uoria 



i cJLib 



er 



tied 



I'm not sure what the typical male reac- 
tion will be on finding that the new editor 
of his favorite ham magazine is a woman. 
However, I promise to maintain my "cool" 
and not put a lace border on the magazine- 
I will continue the present policy of bringing 
you the best possible articles each month. 
Keep me in line, fellows, and if I don't give 
you the kind of magazine you want, let me 
know. 

For a brief backround, I was first licensed 
in 1956 as KH6CKO, then moved to Den- 
ver in 1962 and became W0HJL, and am 
now W1EMV. I hold a General Class li- 
cense, but am working toward the Extra 
at the earliest possible time. My background 
has been primarily as a wife and mother, 
but math and physics has constituted a good 
part of my educational background; mainly 
in the field of statistics and data processing. 
I am not an engineer, by any means, but I 
have done a lot of building and experiment- 
ing. When in doubt, I shall consult with 
someone who has an engineering background. 
In any case, my husband is gone, my chil- 
dren are grown, and here I am. 
So much for the personal side of Kayla, 
I was one of the "save 11 meters" group, 
way back when. Since we lost the fight, I 
have not paid too much attention to what is 
going on on 27 MHz. Recently, a ham friend 
with CB equipment let me listen in on the 
CB band, I was completely stunned by what 
I heard. Calls like, **This is the 'Barefoot 
Boy* calling 'Yankee Pirate*, come on in 
Tankee Pirate' and talk to the ^Barefoot 
Boy*/' I feel certain these calls were not 
issued by FCC, Meantime, in the background, 
many legitimate CRers were trying to get 
through the QRM to deliver messages which 
were legal on CB channels. One poor com- 
pany was trying to contact one of his trucks 
which was located about a mile away, but 
the long skip was in and a relay was finally 
accomplished by a station in South Carolina. 
So much for the efficiency of 11 meters for 
ground wave when the sun spots rise. The 
choice of CB frequencies was definitely a 
mistake. 



I wonder what will happen when the sun 
spot cycle gets to a peak and our CB signals 
(even the legal 5 watters) begin skipping 
around the world. We must remember that 
other countries, especially in South America, 
still vise 11 meters for ham band only opera- 
tion. I remember in 1958 working a station 
in Kansas (I was in Hawaii) on 10 meters 
with less than & watt The CB QRM on ham 
bands in other countries could lead to an 
international incident of the first water, 

My first reaction to the aforementioned 
illegal CB operation was absolute horror. 
Amateur radio gave up 11 meters for this? 
Then I began listening more closely to our 
own ham bands, and came to the conclu- 
sion that before we throw more stones in 
the direction of the CB people, perhaps we 
had better clean our own doorstep* 

Disregard for regulations, flagrant viola* 
tions of the rules, malicious interference, and 
just plain discourteous behavior seems to be 
the "in" thing these days. The AM operators 
who deliberately QRM a SSB round table 
night after night is only equalled by the 
SSBers who delight in creating QRM for the 
AM stations. I feel sure AM will not be 
eliminated from the amateur bands in the 
near future, nor do I feel it would be right 
to eliminate this mode at this time, The two 
modes are, indeed, incompatible, and we 
are simply going to have to find a means for 
peacefully getting along with each other. 
Continuing to make war on each other is 
not going to solve any of the problems. 

The restricted frequencies created by in- 
centive licensing is not going to improve the 
situation ( so it becomes more necessary for 
us to find a solution to living together, 

The letters column this month has a com- 
plaint about deliberate QRM of ARRl/s 
code broadcasts. After reading this letter, 
I decided to listen and see for myself. I'm 
afraid the complaint is justified. This behav- 
ior is not only discourteous and unjustified, 
but is highly illegal. On 75 meters recently 
we have had an influx of "broadcast" sta- 
tions . . . and I'm not referring to the foreign 

[Continued on page 73) 



73 MAGAZINE 



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HERE'S WHAT HAPPENED 



Subscribers during September and October 
ran into unreasonable delays on our part. We 
are trying to make sure that everyone gets 
every issue they bargained for, but the let- 
ters are still coming in from all over the 
world. While the immediate explanation is 
programming difficulties with a new comput- 
er, the long range explanation is more com- 
plicated. 

It has been quite a while since I have 
written about how things are going with 
73, A letter from Richard, WB2UMH, asks 
what happened to some of the old 73 serv- 
ices such as the Radio Bookshop, 6-UP, 
ATV Experimenter, and the Parts Kits. He 
also wants to know what has happened to 
the old aggressiveness of 73, 

Perhaps I can put this in perspective if 
I go back to the beginning. 

Ham radio grabbed me during my fresh- 
man year in high school* back in 1936, The 
great bulk of my 35c a day lunch money 
went into radio parts during high school. 
I built up a storm and had a wonderful 
time with my own receivers, transmitters and 
transceivers. The code bugged me though, 
and it took several nerve wrenching visits 
to the FCC before I managed to steady my 
hand down enough to pass the code test. 
The only reason I passed, I think, is be- 
cause I merely went along with a friend 
who was taking the test and then, at the 
last minute I decided to give it a try . , it 
didn't cost anything in those days. It was 



easy when I wasn't worried about passing 
and soon I had W2NSD. 

A year later came the war. I joined the 
Navy in '42 and went through what I con- 
sider one of the world's greatest electronic 
schools at Treasure Island, I had joined the 
Navy with the understanding that when I 
graduated from school I would go to work 
for the Naval Research Laboratory in 
Bethesda, but I changed my mind and vol- 
unteered for submarines. During 1943-44-45 
I was in the thick of the Pacific war as 
an Electronic Technician 1/c. Then I was 
"retired" to New London where I taught 
school until the end of the war- 
After finishing college in 1948 I tried 
my hand at being a broadcast engineer- 
announcer at a few stations around the 
country. Then I got into television, putting 
WPIX on the air as an engineer and later 
KBTV in Dallas as a producer-director. It 
was in 1948 that I got interested in ham- 
RTTY. I was very interested. When I got 
a job in 1951 with WXEL-TV in Cleveland 
as a director I immediately latched onto 
their mimeo machine and started publish- 
ing an RTTY bulletin. By the next year 
I was writing an RTTY column for CQ. 

Television was fast turning to formulas 
so I decided to get out of that business. 
Those of you who have read, "Only You, 
Dick Daring * will understand what is wrong 
with that industry. I went into hi-fi manu- 



73 MAGAZINE 



factoring and, starting with nothing but a 
small bank ]oan, built up a million dollar 
business in about three years. Unfortunate- 
ly I am a trusting soul and when the busi- 
ness was incorporated I foolishly did not 
have my own lawyer check the papers. The 
other stockholder took over and in about 
a year managed to bungle the business into 
bankruptcy. Long before the courts could 
help me there was nothing to fight over. 

On January 5th, 1955 Cowan talked me 
into taking over the editorship of CQ. The 
magazine was in bad shape and losing a 
good deal of money every month. Perhaps 
I could save it. Inside of a year it was in 
the black and by the second year it was 
making a handsome profit, on the order of 
$100,000 a year. 

Cowan and I had our problems. I wanted 
to change the magazine, dropping the many 
monthly operating news columns and con- 
centrating on contruction and technical 
articles. He didn't want it changed. I should 
have left in 1958 when I realized that it was 
hopeless, but it is awfully difficult to make a 
major change like that when you really don't 
know anything much better to do. 

By 1959 things were very bad and on 
January 5th 1960 we parted company. I 
went to work with a friend in an advertis- 
ing agency, but the more I thought about 
starting a new ham magazine the better the 
idea sounded to me. In May I quit the 
agency and rented a little two room office 
up over a small grocery store in the out- 
skirts of Brooklyn. I bought a mimeo ma- 
chine for promotion letters and started to 
work. I tried for three months to find a 
wealthy ham that was interested in backing 
the magazine, but no dice. So I sold every- 
thing I had that would bring in money and 
got enough together to put out the first 
issue of the magazine. I wrote to old friends 
for articles and started selling subscriptions 
through radio clubs and at conventions. 

The first issue came out in October 1960. 
It was priced at 37c on the cover and a 
subscription was $3 a year, $30 for life. In 
January 1961 I married Virginia and she 
helped with cutting subscription stencils. I 
worked about sixteen hours a daw seven davs 
a week. It was over a year before we could 
afford our first paid employee. We moved 
the magazine into a small apartment with 
us in another section of Brooklyn. When 
our one year lease expired we moved up 

{Continued on page 74) 



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FEBRUARY 1968 



— 



George W, Jones WlPLJ 

12 Traill Street 

Cambridge, Massachusetts 02 1 38 



An Integrafed Circuit Electronic Counter 



Direct Decimal Readout to 10 MHZ 



A digital frequency counter is a useful, 
though not common, piece of equipment in 
the ham shack. The writer built a counter 
many years ago using old fashioned vacuum 
tubes in order to place high in the ARRL 
Frequency Measuring Tests. The unit only 
worked up to 100 kHz, but was adequate 
for the intended purpose. The recent 
reduction in the prices of plastic encapsu- 
lated integrated circuits prompted the writer 
to see if a better unit could be built with 
transistors and integrated circuits. The re- 
sult is a counter which will go up to 10 MHz 
and has every feature a ham could want, 
including direct decimal readout and com- 
pletely automatic operation. The unit shown 
is useful not only during the ARRL FMT 
but also in everyday ham operation, During 
normal operation it is connected to the 
VFO of my transmitter-receiver setup and 
is set on the 100 Hz range, thereby acting 
as a digital "tuning dial" with 100 Hz divi- 
sions; a feature not found on any ordinary 
receiver or VFO. Later, when I go on RTTY, 
it will be useful for setting the transmitter 
frequency shift and aligning the receiver 
converter. 



Principles of operation 

This counter displays the frequency in 
decimal numbers so that the operator doesn't 
have to convert from binary to decimal On 
the one-hertz multiplier range, the cycles of 
the input signal are counted for precisely one 
second, and the progress of the count can be 
watched on the neon lamps. The final count 
is then displayed for one second. The count 
period can be extended to any multiple of 
one second if greater than one-hertz accur- 
acy is needed and, likewise, the display can 
be held for as long as desired. At the end of 
the display period, the counters are reset to 
zero and the process starts over again. On 
the 10-hertz multiplier range the same proc- 
ess is repeated five times a second, on the 
100-hertz range, fifty times a second, etc. 
To avoid confusion on the ten-hertz and 
higher ranges, the neon lamps are not lighted 
during the counting period and are, there- 
fore, seen only displaying the final count. On 
the 10-hertz range, the display blinks five 
times a second, but on the 100 Hz and high- 
er ranges, it appears continuous and appears 
to change immediately if the input frequency 






•.-. oS% 




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■M&<- 



#3SI*»*r' 




^^ffflfcif ■'''■£ V. 






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Front view of the integrated-circuit frequency counter. The neon counting decades are on the left, count 
controls are on the right, 



73 MAGAZINE 



INPUT A- 

INPUT fi - 

6.3V GOHz- 



n- 



INPUT 
SELECTOR 



CONTROL 
SECTION 



RESET OUT 

+200 
OUT 

SIGNAL OUT 

GATE 
OUT 



SELF-CHECK FREQUENCIES 



+ 200 



I MHz OSC 
AND 3 '»l 
DIVIDER 



500 kHz 



FREQUENCY 
DIVIDERS 



O 

O SI 



6 
+22 (AEG) 



6 

63V 
60 Hz 



I 



IKz t 
10 Hi t 
60 Hi, 
100 Kz» 
I hHJC, 
OR 

10 kHz 
PULSES 



10 kHz MARKERS 
TO RCVR 



t4 



RESET PULSES 



R +200 

IN OUT 

UNITS 
DECADE 

GATE 



3V 
POWER 
SUPPLY 



I 






CONTROLLED +200 



R +£00 

IN OUT 

TENS 
DECADE 

GATE 



x 



R +200 



IN OUT 

HUNDREDS 
OECADE 

i 

GATE 



A, 



■OTO ALL SECTIONS 



+ 200 



IN OUT 

THOUSANDS 



DECADE 
GATE 



A, 



Fig. 1. Block diagram of the complete integrated circuit frequency counter. Any number of decades may be 
used, but for proper display, the units decade should be to the right, the tens decade to its left, etc_ 



changes. Therefore, it combines the con- 
venience of an analog display with the ac- 
curacy of a digital display. The last digit 
in this case usually vacillates between two 
adjacent numbers because of the one hertz 
per gating period error inherent in a digital 
count. 

The counter consists of three main sec- 
tions. First, a frequency divider divides the 
signal from a 1 MHz standard down to 10 
kHz, 1000 Hz, 100 Hz, 10 Hz, or 1 Hz, as 
required. A time base derived from the 60 
Hz line could have been used but this would 
have limited the accuracy to 0.1% and 
would only have permitted the 10 Hz and 1 
Hz ranges. This section also applies 10 kHz 
markers to the remainder of the frequency 
measuring setup, The 10 kHz pulses are rec- 
tangular in shape and have strong harmonics 
above 30 MHz. Therefore, they might as 
well be used as markers- 
Second, a control section takes the desired 
time base frequency and turns on the units 
counter for the correct length of time. It 
also shapes the input signal, so that the 
units counter will accept it, turns on the 
high voltage supply for the neon lights dur- 
ing the display period, and supplies a reset 
pulse to all counting decades at the end of 
the display period. 

Third, the counter proper consists of as 
many counting decades as the builder de- 
sires, one for each digit to be displayed. The 
units decade is gated by the control section 
and only counts pulses when the control sec- 
tion wants it to. For each ten pulses the 



units decade is allowed to count, one is 
passed on to the tens decade, likewise for 
each ten pulses the ten decades receives it 
passes one on to the hundreds decade, etc. 
The decade counters, after the units de- 
cade, are not gated since they only receive 
pulses if the units decade is supplying them. 
Although the decades count by binary flip- 
flops, suitable feedback circuits make them 
count in decimal instead of binary, A decod- 
ing network and ten transistors allow one of 
ten neon lamps on the decade to be turned 
on to display one digit of the measured fre- 
quency* Each decade can also be reset to 
zero by a reset pulse from the control sec- 
tion. 



Digital integrated circuits 

The counter uses RTL integrated circuits 
because of their low cost. These have been 
described in 73 magazine both in articles 
and integrated circuits, and in two excellent 
articles about IC electronic keyers; therefore, 
they will only be described briefly here, The 
reader who is not familiar with RTL circuits 
should review these references before try- 
ing to understand the counter in detail, He 
might also find it advisable to build the 
"Kindly Keyer", before he builds the count- 
er, as the writer did. Although the counter 
could probably be built and made to work 
by just following the diagrams, a previous 
knowledge of RTL circuits, gained by build- 
ing a simpler device, will help in trouble 
shooting. 



FEBRUARY 1968 



Oscillator and frequency dividers 

A 1-MHz crystal oscillator is used as the 
main frequency standard at WIPLJ. One 
MHz is used instead of the usual 100 kHz 
because a 1-MHz crystal gives better stability 
than a 100-kHz crystal if one wants to pay 
a reasonable price for the crystal This is 
probably because the 1-MHz crystal can be 
AT cut. The oscillator and a divider to 500 
kHz are mounted in a separate box so that 
the oscillator can be kept on all the time 
for better stability. Also, 500 kHz can be 
used for other purposes including future 
plans to use it to synchronize a phase-locked 
oscillator for the first conversion of the re- 
ceiver. If the builder already has a frequency 
standard, it is not necessary to build an- 
other crystal oscillator for the counter— the 
existing one can be worked in easily. Con- 
versely, if the builder is interested in fre- 
quency measurement but does not yet want 
to build the counter, he can build the oscilla- 
tor and the dividers down to 10 kHz and at 
least have markers for his receiver. The 
oscillator and first divider are shown in 
Fig, 2, 

The remainder of the frequency divider 
section, Fig, 3 5 consists of 2;1 and 5:1 di- 
viders. The 2:1 dividers are simply J-K 
flip-flops; the 5:1 dividers are J-K flip-flops 
with an RC network and inverter on the set 
input which only allows every fifth input 
pulse to produce an output pulse, 

The 5:1 divider can be best understood 
from the diagram and waveforms of Fig, 4. 
Without an input signal, the inverter input 
is held high by the connection to positive 
voltage thru R x , The inverter output is, 
therefore, low so that low appears on the set 
input of the flip-flop. If the O output of the 
flip-flop is initially high, the first negative 
going transition on the toggle input will make 
it go low. This change will be passed on to 
the inverter through C ± and this will make 
the set input go high so that the O output 
cannot go low again when more input pulses 
come in, C x will charge through R 1 and, after 
a delay, the inverter output and the set 
input will go low again so that the flip-flop 
can respond to an input pulse. If the divider 
is adjusted correctly, it will pass every fifth 
input pulse, Other division ratios can be 
obtained, and maybe it would work with a 
division ratio of ten, but the ratio of five 
makes the division ratio very stable* In fact, 
it does not go out of adjustment for a change 
in the supply voltage from 3.0 to 4,0 volts. 



l20-243pH 
CTC 2Q60-6 

2N339I 
10 02 




+3*5 
O 



500 kHz 
OUTPUT 




Fig, 2- The oscillator and 2:1 frequency divider used 
with the decimal counter. This unit was built into a 
separate box and may be used for obtaining markers 
as described in the text. Although the FET is a Mo- 
torola 3 N 1 26, an MPF-105 is less expensive and 
would probably work. IC1 is a Fatrchild 923 or one- 
half a Motorola MC-790-P; IC2 is a Fairchiid 900 
or one-half of a Motorola MC-799-P. 

The first three 5:1 dividers are identical 
except for time-constant values. The output 
of the 10-kHz divider is fed through a buffer 
to the station receiver and frequency mea- 
suring equipment. The markers are very 
strong through 30 MHz, the limit of the au- 
thor's receiver. If the receiver calibration 
cannot be trusted to 10 kHz, the 50-kHz 
test button, shown in dotted lines in Fig- 2 
and not used by the author, can be provided. 
Pushing this button makes the 50-kHz mark- 
ers louder and the other 10-kHz markers 
turn into 25-kHz markers. The counter prop- 
er does not read correctly while this is being 
done, but this doesn't matter since identify- 
ing the markers is done separately from 
making the final count , 

The divider form 500 Hz to 100 Hz uses 
a discreet high-beta transistor instead of a 
gate, so that a higher resistor value and, 
therefore, a smaller capacitor value can be 
used* The dividers to 10 Hz and 1 Hz use 
decade dividers, with four J-K flip-flops 
in order to avoid even larger capacitors. 
This type of circuit could have been used 
for all the dividers and would have elimi- 
nated the need to adjust the dividers. The 
circuit of these dividers will be described 
in the section on the counting decades which 
use the same circuit 

The switch, S 1? selects the divider frequen- 
cy whose period is equal to the desired gate 
time and is calibrated in factors, by which 
the counter reading must be multiplied, 
rather than in gate time. The X60 position 
takes the time base from the ac line instead 
of the dividers, and is useful in adjusting 
the dividers. For example, to adjust the di- 
vider whose output frequency is 50 kHz the 
input switch is set to 50 kHz, the multiplier 



8 



73 MAGAZINE 



switch to 60 and the counter should read 
833, This reading will jump around a bit, 
due to instability in the ac line frequency, 
but the reading for the 10 -kHz divider will 
only vacillate between 166 and 167. 

Control section 

The input selector switch, S 2 (Fig. 5), 
selects the desired input which can be either 
a signal input for measurement, or one of 
the divider outputs for self checking, IC 8 
and IC<j can be regarded either as an ampli- 
fier with positive feedback, or as a flip-flop. 
They make the signal into a rectangular 
wave with sharp edges and reject noise 
which may appear on the input signal. At 
any instant of time, either IC 8 or IC 9 will 
conduct, but not both at once, because the 



one that is conducting turns the other one 
off. The positive half cycle of the input sig- 
nal will make IC 8 conduct and once it is 
turned on, the high output from IC 9 will sup- 
ply holding current through R 4 to keep it on. 
The negative half cycle will then over- 
come this holding current and turn off IC 8 
whereupon the holding current will be re- 
moved and IC 8 will continue not to conduct. 
A small amount of noise riding on the input 
signal will not be able to overcome the hold- 
ing current and will, therefore, not make 
the circuit change state. The resulting rec- 
tangular wave is fed to the units decade at 
all times and the necessary gating is done 
in the first J-K flip-flop of the units decade, 
Provision for gating already exists in the 
J-K and it is simpler to use it than to do the 
gating in the control section, 



rfT 


s 





500 - 


T 




kHl "^ 




INPUT 






r 


c 





+M O 




EACH IN4I4B OR IN9I4 



ALL FLIP-FLOPS ARE FAIRCHILD pA923 OR 
1/2 MQTWOLA MC-790-P 



+3-5 




i --SI --- 



I 




TO BASE 
A3 



OF 



o 

o 
o 
o 



I Hi 
10Hz 
KX> He 
IkHf 

K)hHi 



O+J-0 1 

i 1 



TO CONTROL 
SECTION 




OIHl 



10 Hi 



Fig. 3. The 

Fairchild 9 
MC-799-P. 



frequency dividers used in the IC counter. Integrated circuits ICl through IC5 are one-had of 
I4's or part of Motorola MC-789-P or MC-724-P; IC6 is a Fairchild 900 or one-half a Motorola 



FEBRUARY 1968 



INPUT 



^^ I i ^^ | i — * 1—1 I I ^™ ■- 1 



WVERTER 
WPUT 




INPUT O 



INVERTER 
OUTPUT 




DIVIDER 
OUTPUT 




O OUTPUT 



Fig. 4, The basic 5:1 frequency divider using a J-K flip-flop, and RC circuit and an inverter, along with the 
waveforms. 



The remainder of the control section can 
exist in either of two states, count or dis- 
play. We will discuss these quiescent states 
before we examine how it gets from one to 
the other. In the count state the 1 output of 
IC 7 is high and the O output is low. If Si is 
not in the XI position, the high 1 out-put of 
IC T turns on Q 3 and turns off Q 4 , thereby 
turning off the neon lamps. The low O out- 
put of IC T goes to the gate input of the units 
decade and allows it to count* It also turns 
off Q x so that the "gate on" light will be 
illuminated and it per its the "gate pulse" 
light to be turned on if a gate pulse is pres- 
ent. The opposite conditions exist in the dis- 
play state. Power is applied to the neon 
lamps through Q 4 , and a high output is sup- 
plied to the gate so that further counting 
cannot occur, and both Qj and Q 2 are turned 
on so that the two gate lamps are shorted 
and not illuminated. 

To understand how we change state, as- 
sume we are on display and S 3 is in the auto- 
matic position* ICj and IC 2 form a mono- 
stable multivibrator which supplies the reset 
pulse and the trigger for IC 7 , The positive- 
going edge of the rectangular wave from 
the frequency dividers turns on ICi momen- 
tarily and this makes the output of IC 2 go 
high. Furthermore, this holds ICj on until 
R 2 charges up C 2 again, whereupon the out- 
put of IC 2 goes low again. The result is a 
short pulse which occurs once every timing 
period. Since we are on display and auto- 
matic, this pulse will be passed by IC 3 , IC 4 , 
IC 5 , and IC 6 , inverted each time, and appears 
as a high pulse to reset the counters. The 
trailing edge of the pulse from IC 2 will tog- 
gle IC 7 , putting us in the count mode, The 
next pulse from IC 2 will not reset the coun- 
ters because IC 4 has a high input from 



IC 7 and, reset can only occur if all three 
inputs to IC 4 are low. The trailing edge of 
the pulse still toggles IC T , however, and we 
are in the display mode; displaying the 
number of input pulses that occurred be- 
tween two timing pulses. 

The switch, S 3 , is used if you want to 
count, or display, for a multiple of the basic 
timing period. The switch itself does not 
switch the counter to display or count, since 
only the timing pulses can be allowed to do 
this; rather, it prevents the counter from 
going into the other state. The "display" po- 
sition of this switch is useful if you have 
just made a critical count and want to hold 
it a few seconds to make sure of writing 
it down correctly. It is also useful if the cir- 
cuit for blanking the neon lamps isn't work- 
ing or isn't yet built and you want to make 
a reading on the higher ranges. In this case 
it is difficult to read the display on the auto- 
matic position because you will see both the 
counting and the display, but placing S a on 
"display" will hold the last count and allow 
you to 'read it. The switch can be thrown to 
"display" either during count or during dis- 
play- In either case, a timing pulse will still 
switch IC T from count to display at the right 
time, but the next timing pulse will not put 
it back on count due to the high level on 
the clear input. Also, the counter will not 
be reset due to the high input of IC 4 which 
will hold its output low. 

The count position of S 3 is normally used 
only on the XI position of S x , and is used 
when you want a gate time of several sec- 
onds for an error of less than one Hz. This 
is useful in the ARRL Frequency Measur- 
ing Tests where it is desirable to use a 10- 
second gate time in order to obtain an ac- 
curacy of 0,1 Hz. With this arrangement, 



10 



73 MAGAZINE 



if you start a ten second run and the signal 
starts to fade, you can stop the test at the 
next timing pulse by throwing the switch 
to display and still obtain a meaningful 
reading. To make a ten second run, you 
start with S ;t on display, and throw it to 
count when everything is ready. The next 
timing pulse will put you in the count mode, 
but the next one will not put you back on 
display- 
Each timing pulse will flash the "gate 
pulse" lamp once, and after it has flashed 
ten times, you put S 3 back on display. The 
next pulse will put the counter on display 
and you will be able to read the frequency 
in tenths of hertz. With a little practice, you 



will find that running a multiple second 
count is much easier than reading about it. 
In wiring the counter it should be remem- 
ered that the supply to the neon bulbs is 
a 200-volt square wave because of the lamp 
blanking circuit, and also, the collectors of 
Q x and Q-> (Fig. 5) have 60-volt pulses on 
them since they turn on neon lamps* Both of 
these must be kept away from the inputs to 
the IC's; otherwise, erratic operation will re- 
sult. In particular, the 200-volt lead to the 
counters must not be cabled with the signal 
and gate inputs to the counters and the leads 
to Ij and 1 2 must be kept at least an inch 
away from the leads of S a , If the counter 
shows any erratic operation which cannot 



FROM SU 




INPUT A O- 

INPUT B O- 

63V SOMfO 



FROM 
FAEQ 

OiV. 



— ] ic4 jo — Kp>o kVx> 



RESET 
TO ALL 
DECADES 



H- COUNT 



+3,5 O — WV 
Ik 



DtSPLAY 



IC 7 




H- DISPLAY 



GATE 
"O TO UNITS 
DECADE 



+ 20GO 



TO SI, 





04 
2N3440 



03 
2N344Q 



-+2O0 
-°T0 ALL 
DECADES 



+ 200 




NE2 



rn 




220 k 



II 

GATE ON 



m 



SIGNAL 

OTQ UMTS 
DECADE 



+ZOO 



2.2 k 




NE2 







220k 



12 

GATE PULSE 



fT7 



Fig. 5, The control section of the digital frequency counter, ICl is a one-half a Fairchild 914, one-fourth a 
Motorola MC-724-P or one-third a Motorola MC-792-P. IC4 is one-third a Motorola MC-792-P. IC2, IC3, 
ICS, and 1C9 are one-sixth of Motorola MC-789-P, one-fourth of Motorola MC-724-P, or one-half of Fair- 
child 914, IC6 is a Fairchild 800 or one-half a Motorola MC-799-P, IC7 is a Fairchild 923 or one-half a 
Motorola MC-790-P. QI and Q2 are 2N3877's or Poly Pak 2NI893'*. 



FEBRUARY 1968 



II 






All of the count-control 
circuitry is mounted on 
the large chassis to the 
left. The small perfor- 
ated boards on the 
right each contain one 
decade counter. 





«£x 







_ 



be easily explained, the blanking circuit 
should be disabled by grounding the base of 
Q 3 so that the lamps are on continuously, 
and Ij and I 2 should be shorted to ground. 
A test can then be made to see if the trouble 
still exists. Except for these precautions ? no 
other difficulties should be encountered with 
the unit. 

Counting decades 

Fig. 6 shows the circuit on one counting 
decade, including neon lamp drivers, The 
gate input on the units decade is connected 
to the gate output of the control section, 
but the gate inputs on the other decades 
must be grounded since each must accept 
any pulses put out by the proceeding decade. 
The actual counting is done by four J-K 
flip-flops and, with the help of the table 
shown, the reader can follow the count as 
an interesting exercise. The input pulse fol- 
lowing the ninth count makes the decade 
go back to zero and passes a negative tran- 
sition on to the next decade making it count 
once. 

IC 5 through IC 12 are needed to amplify 
the voltage output of the J-K flip-flops. The 
J-K's give only one- volt output with light 
external loading due to the fact that they 
internally load their own outputs. This was 
not found sufficient to drive the resistor 
gates used for the neon lamp drivers. An 
inverter, however, gives almost full supply 
voltage when lightly loaded and drove the 
resistor matrix satisfactorily. 



It is necessary to use discrete transistors 
to drive the neon lamps at the present state 
of the art, but these are not expensive, ex- 
pecially if Poly Paks* 2N1893s are used. 
The transistors are used as shunts scross the 
lamps. This makes gating simpler and also 
limits the voltage across each transistor. For 
a given count one lamp must be on and the 
other nine off. The driver for the desired 
lamp must have low level on all its inputs 
so that the transistor will not conduct, allow- 
ing the lamp to light. The other nine drivers 
must have high level applied to at least one 
input; this will be sufficient to extinguish 
the lamp, regardless of what appears on the 
other inputs. The gating of the lamps could 
have been done entirely with IC's but this 
method was found to be simpler and cheap- 
er, at least at the present state of the art. 



Count 



A 
B 



B 
A 



C 
D 




I 

2 
3 

4 
5 
6 
7 
8 
9 



H 
L 
H 
L 
H 
L 
H 
L 
H 
L 



L 
H 

L 
H 

L 
H 

L 
H 

L 
H 



H 

L 

L 

L 

L 

H 

H 

L 

L 

H 



D 


E 


F 


G 


H 


C 


F 


E 


H 


Qp 


L 


H 


L 


H 


L 


H 


H 


L 


H 


L 


H 


L 


H 


H 


L 


H 


L 


H 


H 


L 


H 


H 


L 


L 


H 


L 


H 


I 


L 


H 


L 


H 


L 


L 


H 


H 


H 


L 


L 


H 


H 


L 


H 


L 


H 


L 


L 


H 


L 


H 



Table I, Truth table showing the proper levels on 
each of the logic lines of +he decade counter In 
Fig* 7. 



12 



73 MAGAZINE 



RESET O 



INPUT O 



GATE 



B 




O OUTPUT TO 
NEXT DECADE 



220 k RESISTORS ARE I/2W 

RESISTORS NOT MARKED 

ARE 10 k 1/4 W 





OH H 



2201 




Fig, 6- A typical counting decade. In this circuit integrated circuits 10 1 through IC4 are one-half Mo- 
torola MC-790-P's or Fairchlld 923V IC5 through IC9 are one-sixth Motorola MC-789-PV one-fourth Mo- 
torola MC-724-P's or one-half Fairchild 914V All transistors are 2N3877's or Poly Pales 2NI893V All neon 
lamps are NE-2V 









In testing the decades, +200 volts must 
not be applied unless all transistors, which 
are in place, have neon lamps across them* 
Otherwise, if a transistor is not conducting, 
the collector voltage rating will be exceeded 
since there is no neon lamp limiting the 
voltage- Also, if +200 volts is applied to a 
decade but +3.5 is not, all lamps should 
light since the logic circuitry only acts to 
short out the undesired lamps. No harm is 
done by this and it is a quick way to check 
the lamps and driver transistors. If a lamp 
does not light under this condition, its 
driver transistor should be suspected first. 

Power supply 

The counter, as shown in Fig* 6 ? requires 
about one ampere at 3.5 volts and 40 mA at 
200 volts. Neither supply needs to be regu- 



lated and the IC's will work on any voltage 
from 3.0 to 4,5 volts, although 3,6 ±10% 
is recommended by the manufacturer. The 
power supply used by the author is shown 
in Fig. 7. An 8-amp transformer was used 
because it didn't cost much more than a 
2-amp one in the same series. The 2-amp 
unit would probably work and would save 
space and weight. For the 200-volt supply, 
anything from 150 volts on up would work, 
although with anything much over 200 volts, 
the 220K collector resistors must be in- 
creased or a dropping resistor must be pro- 
vided. If this voltage is taken from a supply 
powering other equipment, it must be re- 
membered that the current drawn will be 
a 40 mA peak square wave at 5, 50, 500, 
or 5000 Hz which may cause a buzz to be 
heard on the other equipment. 



FEBRUARY 1968 



13 



H 



BARRY 
12JB-1 



SARKES-TARZ1AN 
20-C 




115 VAC 



+ 3 



27.500 |iF 

5V 

MALLORY 

CGZ752U5DI 



SARKES-TARZIAN 
20-C 



Fig 7. Three-volt power supply for use with the in- 
tegrated circuit frequency counter. A truth table 
showing the proper levels on each logic line are 
shown in Table I. 

Construction 

The individual counting decades are built 
on See-Zak M M-492 boards and the remain- 
der of the unit on a See-Zak MM- 5 12 board 
mounted on See-Zak R-25 and R-212 rails. 
See-Zak M-25 terminals are used for the 
larger components, including the Fairchild 
IC's. The hole spacing on these boards is 
0.2" whereas the Motorola IC's require 0*1" 
spacing; therefore, seven extra He inch holes 
must be drilled for each Motorola IC inbe- 



tween existing holes. Connections to the 
Motorola IC's are made with #26 bare wire 
covered with Teflon spaghetti. No other con- 
struction details are given since the writer 
is more interested in circuitry than packag- 
ing and other builders will probably have 
ideas of their own. The use of printed cir- 
cuits would be ideal. 

• . . W1PLJ 

*Poly Packs, Post Office Box 942 A, Lynn field, Massa- 
chusetts 01940. 

References 

1. Skeen, "Low Cost Precision Frequency Measure* 
ment", QST, January, 1065, p. 32, 

2. Brassine, "An Electronic Counter for Amateur Use," 
73, December, 1966, p. 20. 

8. Pickering, "The Mirro-Ulttm&ffe-', ?3, June, 1966, 
p. 6. 

4. Daughters, "The Kindly Kever", 73. July. 1966, 

p. 46. 

5. Lancaster, "Using New Low Cost Integrated Cir- 
cuits**, Electronic* World, March, 1966, p. 50. 

6. Olson, "Micro-Logic for Non -Logical Users' 1 , 73, 
June, 19fi7. p. 58. 

7. Sliding, "An IntPtfratedSCircuit Frequency Counter," 
7S S November, 1967, paffe 9. 



HOW COME? 



I have two cubical quad beam antennas in 
my yard. Each is on a forty foot tower. They 
are separated by about eighty feet. Hundreds 
of times I have tuned in a signal on the 
two element quad, measured it with the S 
meter, and then flipped the co-ax antenna se- 
lector switch to the four element quad, and 
again measured it* The difference in the S 
meter reading is usually one S unit, or, ac- 
cording to the usual calibration of S meters, 
about six dbs. This, I suppose, is what it 
should be, A Collins and a Swan were used 
in measuring. Remember, both quads are 
identical in construction, measurements, 
height, and closeness to foreign objects. 

The only difference between the two is 
that the 4 element quad uses two directors 
and the two element quad uses no directors. 
Now, I can switch to transmit, and contact 
manv stations, These amateurs almost invari- 
ably report the signal from the 4 element 
quad from two to three S units greater than 
on the two element quad. This is from 
twelve to eighteen dbs. 

Obviously there is not that much differ- 
ence in the two antennas, so where does 
the extra punch of the four element quad 
come from? The difference between the four 
and the two element quad will almost in- 
variably measure this amount, regardless of 
the type of receiver the amateur is using. 



How can we account for this difference? 
Is it the vertical angle of radiation? Is it the 
aperature, or the capture area? Is it a combi- 
nation of several factors? 

One thing is obvious. If we put 100 watts, 
let us say, of ri. energy into an antenna, 
it will be distributed in various ways. If the 
antenna is a vertical, it will be distributed 
equally in all directions. If it is a beam anten- 
na, then a certain direction will be favored. 
The greater the F/B ratio, the greater the 
gain in a certain direction. We cannot get 
something for nothing. We have to take it 
off the back if we want to put it out front. 
Then there is the actual "cone" of the radi- 
ation pattern. A two element quad possesses 
a much broader cone than a four element 
quad. Hence the actual energy is concen- 
trated in the favored direction much more 
in the four element quad than in the 
two element quad. This is apparently not 
true in the reception of signals. Evidently the 
old adage that "A good receiving antenna is 
an equally good transmitting antenna", is 
not entirely true. In our case, it would ap- 
pear that, even for a quad, it can be a better 
transmitting antenna than a receiving anten- 
na. 

L W. Van Slyck W4YM 

406 Bon Air Ave. 

Temple Terrace, Florida 33617 



14 



73 MAGAZINE 




Classic 10-15 

A new beam for 10 and 15 meters. 
Revolutionary broad band capacitrve 
matching* Full power rated. Weather- 
proof metal encased traps, Light- 
weight: 27.5 lbs. assembled. May be 
stacked with 20 and /or 40 meter 

beams - |(i| P.nd.) 

Classic 

Hard working for extra gain on 10. 15 
and 20 meters. Wider element spacing 
and improved clamping. Broad band 
capacitive match* Full power rating. 
Weatherproof traps for constant fre- 
quency stability* * (Pon Pend#) 





TA-33 

Excellent results for f ul I ham band* 
width. Full power rated for 10, 15, 
and 20 meters. Strengthened center 
sections of the 28' maximum length 
elements. Weatherproof traps for con- 
stant frequency stability. May be 
converted to 40 meters. 

TA-33 Jr. 

A low power beam with "authority/' 
Rated at 300 watts AM/CW, and 1000 
watts P.E.P. on SSB. May be converted 
to MP-33 for higher power rating. Max* 
element length is 26* 8" 



For more information on these, or any 
of Mosley antennas see your nearest 
authorized Mosley dealer, or write, 

4610 North Lindbergh Blvd. Bridgeton, Mo. 63042 



W, R. MeCullagh VE3DAN 
73 Simco Street 
Toronto, Ontario 

Canada 



An Amateur Tries I Cs 



There is no doubt that the greatest ad- 
vance in electronics since the transistor is 
the integrated circuit, where a dozen or more 
transistors, resistors, and diodes are put in 
a can no larger than a single transistor. 
The whole lot in fact on a little chip of 
silicon less than an eighth of an inch across* 
Perhaps the day of Dick Tracy's wrist watch 
size radio is almost here. 

Heath has already announced kits using 
these circuits, and other manufacturers are 
undoubtedly thinking along the same lines, 
so it behooves the experimentally-minded 
amateur to learn something about this 
latest development. 

There have been some excellent articles 
in Electronic World, Radio Electronics, and 
73 r which should certainly be consulted, as 
well as the manufacturer's literature. The 
RCA specification sheets and application 
notes are particularly instructive. My indebt- 
edness to the above sources is gratefully 
acknowledged. 

One of the first confusing things about 
IC's is the use of transistors to replace 



capacitors; this gives the circuit a strange 
and unfamiliar look which takes a while 
to get used to. 

It would be impossible to incorporate large 
capacitors or resistors on the small chips, so 
transistors are used instead. Where large 
capacitors or resistors are necessary, they 
are connected externally, as are coils and 
transformers. 

The most commonly used arrangement in 
the linear integrated circuits, is the emitter- 
coupled pair, with the emitter current sup- 
plied by another transistor. The input is 
usually differential and the output may be 
single ended or push-pull. 

This approach would be impractical with 
individual transistors, but because all the 
components are on the same piece of silicon, 
their characteristics are similar and are 
closely matched over a wide temperature 
range. The basic system is shown in Fig. 1. 

One of the simplest IC's and the easiest 
to understand, is the Fairchild ^A 703 C 
(or m7703 as it is now designated). Inci- 
dentally, there seems to be some disagree- 



Thls photograph dra- 
matically illustrates the 
number of transistors, 
resistors and diodes in- 
corporated in one RCA 
CA 3012 integrated cir- 
cuit. The CA 3012 IC is 
shown on the left for 
comparison. 




















16 



73 MAGAZINE 



NPUT NO. \ O 




O INPUT NO. 2 



Fig. L The basic emitter-coupled pair. This approach 
is difficult with discrete transistors, but with the IC t 
all the components are on the same silicon chip, and 
their characteristics are similar and remain matched 
over wide temperature ranges. 

ment on the numbering of the pins. The 
numbering used here is from the Fairchild 
specification sheet dated August 1966 
(Fig- 3). 

The ^7703 is classed as an rf and if 
amplifier and is one of the least expensive 
of the Fairchild IC's at about $4.50 each 
in small quantities, A diagram of the ^7703 
is shown in Fig, 3. As will be seen, there 
are two additional transistors connected as 
diodes; I don't think we need to go into 
the theory behind them, but can use the 
simplified diagram for our purpose. For 
further technical information see the refer- 
ences. Although the m7703 is listed as an 
if and rf amplifier, it can also be used as 
a do amplifier. 



INPUT 
(HI) 



INPUT 
(LOJ 




+V 



OUTPUT 



DECOUPLING 



GND 



INPUT 
tM|J 



DECOUPLING 




OUTPUT 



INPUT 
(LO) 



GND 



Fig. 7. External connections to the Fairchild ju703 
(^7703), and RCA 3011 and 3012, The internal cir- 
cuit of the ju703 integrated circuit is shown In Fig, 
3; the CA 3012 is shown in Fig. 4. 

For experimental purposes the ^7703 was 
mounted on a small piece of bakelite. Double- 
ended Cambion 2044 terminals which (as 
they always say in radio articles) I just 
happened to have a thousand of in the junk 
box, were forced into slightly undersized 
holes in the board so that it wasn't neces- 
sary to use special setting tools. The IC 
was soldered to these pins and the wiring 
was done underneath. 

The m77G3 has a rated working voltage 
of 12 volts but the first one blew on 9% 
volts, so a limiting resistor was used in the 



power supply and the current was kept be- 
low 3 mA. A look at the chip in the dis- 
mantled IC makes one wonder how they 
can handle any power at all! The chip 
doesn't seem to be much larger than the 
head of a pin and a high-power glass is 
needed to see the actual components* 

To familiarize myself with the ju7703 and 
to be sure of not overloading it, I used a 
Weston photoelectric cell in the input A 
few microamps in gave an output in the 
milliampere range* Using a tuned-input cir- 
cuit, it became a very sensitive absorption 
meter. 



+ v 



IN 




our 



NOTE 

01 4 Q2 ARE 
CONNECTED 
AS DIODES 



Fig. 3. The circuit of the Fairchild ^703 (ju7703). 
Basically, this is an emitter-coupled pair (Q3 and 
Q4J with a constant current source (Q5). Tran- 
sistors Ql and Q2 are connected as diodes. 

Just looking at the RCA 3000 series of 
IC s makes one drool and wish for a pocket 
full of cash to get the whole series. The 
only trouble is that they seem to be in 
short supply, I have been waiting for months 
for some I ordered from Chicago and they 
haven't arrived yet. 




The test setup used for checking out the capabilities 
of the RCA 3012 integrated circuit, 



FEBRUARY I96B 



17 



■V 



Type 


Circuit Application 


dB Gain 


Freq. MHz 


MfC 


Price 


Noice dB 


CA 3000 


Differential Amplifier 


37 


30 


RCA 


$4.70 


— 


CA 3001 


Differential Amplifier 


19 


video 


RCA 


$6.40 


5 


CA 3002 


Differential Amplifier 


24 


n 


RCA 


$4.40 


4 


CA 3004 


Differential Amplifier 


12 


100 


RCA 


$4.40 


6.3 


CA 3007 


Differential Amplifer 


22 


audio 


RCA 


$6.00 





CA 3011 










$1.55 






Wide band Amplifier 


75 


20 


KV-*A 




8.7 


CA 3012 










$2.25 






Wide band Amplifier 


75 


20 


RCA 


$2.65 




CA 3014 


Discriminators 


75 


20 


RCA 


$3.15 


8.7 


CA 3020 


AF Amplifier 


58 


6 


RCA 


$2.80 





CA 3021 


Low Power Wide band 


56 


2.4 




$3.60 


4.2 


CA 3022 


Amplifiers 


57 


7.5 




$3.15 


4.4 


CA 3023 




53 


16 


RCA 


$2.95 


6.5 


CA 3028 


RF Amplifier 


39 


120 


RCA 


$1.55 


6.7 


M7703 


IF Amplifier 


41 





Fair- 


$4.10 


— 



child 



«* T» 1* 




O*0UT 



txif-iirflo O 4 



Fig, 4. Internal circuit of the RCA CA 3012 inte- 
grated circuit. The signal path through the unit is 
shown by the heavy line. 

Only the larger industrial stock houses seem 
to be handling the ICs s and the types 
stocked are for the large users for defense 
and computer purposes. The RCA line seems 
to be the lowest priced and most com- 
plete of any, 

I was able to get a few RCA CA 3012's 
locally so an if amplifier was constructed 
using two of these. I had planned on using 
ICs in the converter and audio amplifier, 
but I had to settle for an imported audio 
amplifier and a transistor converter, I also 
made an if amplifier using Fairchild m7703's. 
The m7703, because of its fewer pins, was 
easier to work with and needed fewer 



components. After making these up, I dis- 
covered 7- and 9-pin connectors for miniature 
sockets which would have made it easier 
to interchange IC's. 

As this was a preliminary project to see 
how well IC's worked, no refinements were 
considered; they will come later. The re- 
sults obtained with these little jewels were 
truly amazing. 

. . . VE3DAN 




An if amplifier and detector built from two Fair- 
child fi770i integrated circuits. There is enough room 
left on the board for an audio amplifier. 



References 

Radio Electronic** March 1967. 

Electronic* World, September 1964, October, Novem- 
ber, and December 1966, and January 1967, 

Scientific A m e r ica n , N o vember 1965. 

Fairchild and RCA Data Sheet* and Application Notes* 



18 



73 MAGAZINE 














/ 



i 



s 



I 



I 




PRECISION 



VUX&uft 



LS AND ELECTR 



•!£ 



FOR THE COMMUNICATIONS INDUSTRY 




kl 



1634 Linwood i 

PHONE: 405-232-1 



L . 




1 









L 



1 



■ 



rd- Oklahoma City, Oklahoma?* 

-361 - TWX: 910-B31-3I75 



IE 



EL 




mmmtmmmmmmmmm 



Francis A. Spelman WA7CUS 
4317 Northeast 56th Street 
Seattle, Washington 98105 



John Spillane W7UGV 
2010 N.W. 60th St. 
Seattle, Washington 98107 



The Ferris Wheel Antenna 



for 760- and 80-Meter s 







* * ■■ 



5' 4 




2" 0.D, ALUMINUM 

downspout 



45 w ELSOW 
FITTING 



\* 



12' 9* 




H 



3 u 




6 O 

TO 

TUNING 

NETWORK 



Fig. I. A Ferris Wheel antenna cut for 160 and 80 meters. This antenna exhibits 
good efficiency with small size at relatively low height above he ground. 



A recent article describing the use of loop 
antennas in Viet Nam 1 led the authors to 
plan and build the Ferris Wheel antenna de- 
scribed below. The Ferris Wheel is compact, 
inconspicuous, inexpensive, portable (if de- 
sired), broadband, and reasonably efficient. 
Its radiation characteristics are quite good— 
in fact the Army Limited War Laboratory 
found that a vertical loop antenna surpassed 
a low dipole in terms of radiated power 2 . 



Since the lower bands, particularly the 2 
MHz and 4 MHz bands, are transmitted with 
low-hanging amateur antennas, the Ferris 
Wheel seemed an ideal antenna for low- 
frequency work. The antenna is good for 
both short and long skip, since it has good 
radiation characteristics at both low and 
high angles. The Ferris Wheel is an ideal 
field-day antenna, since it requires virtually 
no support on a calm day, and only minimal 



20 



73 MAGAZINE 



TUNING 



367 



RGB/LP 



XMTRO 



f 



1 

30 M ^j^ 
O Ptt 1 



200 
IkV 



dtd- 



COARSE 
TUNING 



RG8/U 



XMTR &■ 






TO ANTENMA 

9 




LOADING 



f- 734 

[U>36?pF IkV 
fj-} IN PARALLEL] 



40O 

IkV 



rti 



rti 



LOADING 



; COARSE 
TUNING 



TUNING 



rti 



* 



^^3€7 
IkV 

rh 



z> 



X 

1 



TO ANTENNA 



^1^400 

_J mv 



(A) (8) 

Fig. 2. Antenna tuning matching networks for the Ferris Wheel antenna. The circuit in A is for low-power 
applications; the circuit in B for high power. 



support on a blustery day. Finally, as a 
permanent antenna, the Ferris Wheel is 
quite sturdy, the model built here having 
survived both small-craft and gale warnings 
with no ill effects. 

The Ferris Wheel antenna (Fig. 1) is a 
loop antenna mounted vertically upon the 
ground. Since the radiation resistance of a 
loop antenna is very small (see Table 1), the 
conductor forming the loop must be made 
as large as possible in order to achieve rea- 
sonable (if disadvantageous) efficiency. In 
order to reduce loss resistance, we selected 
2-inch aluminum downspout as the conduc- 
tor of the Ferris Wheel. Obviouslv, we used 
unpainted, bare aluminum, 

A forty-foot circumference loop antenna, 
made of 2-inch aluminum downspout, will 
have reasonable (17.5%) efficiency at 2 MHz 
and better (70.7%) efficiency at 4 MHz. Con- 
veniently, aluminum downspout is sold in 
10- foot sections. Since radiation resistance is 
proportional to the square of the area of the 
loop 3 * 4n , an octagonal shape was chosen over 
a square shape since the octagonal has 20% 
more area for the same circumference, and 
thus, the radiation resistance is 44% greater. 
Additionally, five-foot lengths of downspout 
are much more convenient to handle than 
ten-foot lengths in a portable installation, 
and 45-degree elbows are readily available 
while 90-degree elbows are not Both elbows 
are listed in catalogs, but the 90-degree el- 
bows are generally missing from the local 
dealers' shelves* 

The capacitive tuning network (Fig, 2A) 
is simple to make and to tune, and it will 
handle powers of several hundred watts. 
The values shown tune the antenna within 
the 160-meter and 80-meter amateur bands. 
For higher power operation, the balanced 
network of Fig. 2B may be used. Tuning this 
network is more difficult, but by no means 
impossible. 



The Ferris Wheel antenna has given ex- 
cellent results, both on 160-meters and on 
80- meters, One evening, on the first try made 
on that band, we made a contact of 400 
miles on 160-meters, and we had several 
contacts on 80-meters, ranging from 3 to 
600 miles. 

The key to success with the Ferris Wheel 
is to maintain low resistance in all joints 
and connections. To achieve this we force- 
fit each joint between the downspouts and 
elbows, and then drilled three holes, approxi- 
mately 120-degrees apart, and then riveted 
each downspout-to-elbow joint (Fig. 3) with 
aluminum rivets. The rivets were inserted 
with a hand riveter, available for about $5.00 
at either a harware store or Sears. Aluminum 
rivets must be used to avoid future electro- 
lysis and corrosion at the joints, At the 
feed point, an inch-and-a-half was removed 
from the center of the five-foot downspout, 
and a paraffined wooden plug was inserted 
in the downspout as a spacer (Fig. 3). Con- 
nection was made to the feedpoint with 




The Ferris Wheel antenna mounted to the side 

WA/CUS's house. 



FEBRUARY 1968 



21 



Fig. 3* Construction de- 
tails of the Ferris Wheel 

antenna* 



\/Z" FLAT COPPER SRAtQ, UN END. DRILL, 
& SCREW INTO ALUM STRAP^ 



DRILL 1/3 HOLES i RIVET WITH . 
M&~ SMALL 5iZE ALUMINUM RIVETS, 




JOINT JETAIL , DOWN SP OUT - T O - 

45 B elbow Fitting 





SECUHE WITH 
ALUM KA1L$ 



PAH fl F F IN - S ATUR ATED 
*OODEM PLUG 



*, 



CENTER SPACER PLUG DETAIL 



DOUBLE ThjCKNESS OF ALUM P|*>E BAND. 
NORMALLY USED TO MOUNT DOWNSPOUT 
TO HOUSE. INSTALL BEFORE INSERTING PLUG. 
OR ILL 1 RIVET TO DOWNSPOUT. 



CONTACT STRAP DETAIL 



cfouble aluminum strap (available to affix the 
downspout to a house) riveted to the down- 
spout as shown in Fig. 3. Half -inch tinned 
copper braid was screwed to the tabs on the 
aluminum strap (Fig, 3) and used to tie the 
loop to the tuning network inside the shack. 
The joints were all sprayed with Krylon 
(after riveting and attaching the braid) for 
weather protection. The loop was fixed to 
the side of the house with five aluminum 
straps, each made of a pair of downspout 
straps, and the loop was spaced 1%-inches 
from the house with square, painted, wooden 
spacers. 

The total time of erection of the Ferris 
Wheel antenna is less than five hours, in- 
cluding the hacksawing, cutting, fitting, drill- 
ing and riveting. The above time includes 
searching for spacer wood in a basement junk 
heap, spacer carving with a dull knife, but 
not paraffin treating, spacer painting, and 
construction of the tuning network. The net- 
work had been built before the antenna was 
raised. Tuning network construction is 
straight -forward (although number 14 wire 
should be used to make all connections ) ? and 
is left to the imagination of the reader. 

The radiation pattern of the Ferris Wheel 
antenna is directional in a horizontal plane, 
and is vertically polarized. Both the hori- 
zontal pattern and the vertical pattern are 
shown in Fig- 4. The patterns shown are 
those of a vertical loop, resting upon a per- 
fectly conducting earth. The patterns do not 
differ substantially from those of a small 
vertical loop in space, and thus imperfect 
ground has little effect on the loop, as long 
as the loop is close to the ground. Patter- 
son's article points this out, and a few mo- 
ments analyzing a loop antenna and its image 
due to a ground plane will substantiate the 
result. Tests made on the antenna at 3,96 
MHz within the state of Washington confirm 
the theoretical pattern. 

The Ferris Wheel is a broadband antenna, 
Using the network in Fig, 2A ? we found that 



once the antenna is tuned midband on the 
75-meter band, VSWR remains with 1.6:1 
throughout the band, But the Ferris Wheel 
is easily tuned, and with the aid of a VSWR 
bridge, it can be adjusted rapidly, Patter- 
son's article shows a VSWR bridge built into 
the tuning unit, and for installations where 
the antenna is not at arms reach from the 
transmitter, a bridge built into the tuning 
unit would be most convenient Since the 
feed point can be anywhere on the loop, the 
antenna feedpoint can be placed convenient 
to the transmitter. Initial tuning (within 2:1 
VSWR) can be made by tuning the antenna 
to maximum signal output in the receiver 
(AVC off), Final tuning is done with trans- 
mitter RF power. 




HORIZONTAL PATTERN 




GROUND 

LEVEL 

VERTICAL PATTERN 

Fig, 4, Patterns lor a small vertical loop antenna, 
resting on a perfectly conducting earth. Tests made 
by the authors appear to confirm that the Ferris 
Wheel antenna pattern closely resembles this theo- 
retical pattern, 

Since our initial tests on the Ferris Wheel 
antenna were made using force-fit joints be- 
tween the downspouts and elbows, and dur- 
ing those tests we had good results from 
distant (12 miles) stations during the after- 



22 



73 MAGAZINE 



Table I. Comparison of antenna size, frequency and efficiency. 





Section 


Radiation 


Loss 




Circumferer 


Frequency 


Length 


Resistance 


Resistance 


Efficiency 




2 MHz 


5 ft 


7.5x 1 0-«I2 


3.53x1 0" a O 


1 7.5% 


40 ft 


4 MHz 


5 ft 


0. 1 2012 


5.00x1 0- 2 fi 


70.7% 


40 ft 


4 MHz 


3.28 ft 


2.30xfO-*fi 


3.28xl0" a n 


4 1 .3 % 


26.24 ft 


7.3 MHz 


3.28 ft 


0.2 590 


8.85x 1 0" 2 fi 


74.5% 


26.24 ft 



noon on 75-meter s, we concluded that a 
force-fit Ferris Wheel would make a useful 
field day antenna for the two dc bands. Per- 
formance is not deteriorated by resting the 
loop on the ground, so long as losses are not 
increased at the feedpoint (from moist earth, 
for example). For the initial tests, our loop 
was rested upon a wooden 4x4 on the 
ground, and the loop leaned against the side 
of a house. In the field, the Ferris Wheel 
could rest on the ground, and lean against a 
tree for support. The five- foot lengths of 
downspout slip easily into the back seat of 
a car, or into the back of a station wagon, 
and the elbows are simple to store and carry. 



Table 2- Material required for the Ferris Wheel 
antenna. 



Part 

Downspout, 2-in diameter, Aluminum, 

10-ft. section 

Elbow, 45-deg M 2-in. diameter, Aluminum 

Strap, downspout mounting, Aluminum 

Rivet, '/g-fn,, Aluminum, small 
Nail, Aluminum, roofing 

1% x 1% x 24-inch unfinished board 
Plastic spray, Icrylon spraycan 
Paint, house (to match QTH decor), 

to paint mounting spacer blocks 
Capacitor, variable, transmitting, 

I ItV, 365 pF 
Capacitor, ganged variable, transmitting, 

I kV, 365 pF each section 
Capacitor, silver mica, I IcV, 400 pF 
Capacitor, silver mica, I kV t 200 pF 
Switch, ceramic wafer, 2PST 
Braid, tinned copper, W-inch 



Quantity 

4 each 

8 each 

14 each 

70 each 
12 each 

I each 

I each 

As needed 



I 



each 

1 each 
each 



I each 
I each 
I each 
6 feet 



The Ferris Wheel antenna can be made 
for higher frequencies than 2 MHz and 4 
MHz. Table 1 lists radiation resistance, sec- 
tion length, and efficiency for a 2/4 MHz an- 
tenna and for a 4/7,3 MHz antenna. At high- 
er frequencies, the advantages of a small 
loop are far outweighed by the advantages 
of other types of antennas, and so the calcu- 
lations are not presented for frequencies 
higher than 7.3 MHz, 

The Ferris Wheel is an inexpensive, sim- 
ple, and effective antenna at 2 MHz and 4 
MHz. It is easily erected for either a perma- 
nent installation or for field dav. It can be 
made of readily available materials {Table 2) 
within an afternoon. 

. . . W7UGV, WA7CUS 



Antenna efficiency is given by 

efficiency =2 R r /(Tt F -f Ri) 
where 

R r = radiation resistance = 3.12xl0*x 

(A) 2 /( Y ohm 
Ei = loss resistance ±± 6,25xl0 _7 x(s) 

(f)Va 

b ss circumference in feet 
t = frequency in Hz 

The logic leading to the above formulas is found in 
reference 4, Chapter 12, Section 10: Chapter 5, Sec- 
tion 17. 



References 

1 Patterson, Kenneth H., "Down-to-earth Army An- 
tenna," Electronics (August 21, 1967), 111*114. 

2 !oc* cit; p, 114, 
ft foe. ciL t p. 113. 

4 Ramo, Simon, et. aL, Field a and Waves in Communi- 
cation Electronics, pp. 288-303. 656-657, New York, 
John Wiley & Sons, Inc., 1065. 

£ King, Ronald W. P., et. al. w Transmission Lines, An- 
tennas and Wave Guides, pp. 224-230, New York, 
Dover Publications, Inc., 1965* 



1 



"iAUJN" 



Tar tftwi^apt*!*** 



WRITE FOP 
TELREX PL 68 



TELREX (Patd.) "BALUN" FED lf IN VERTED-V" ANTENNA KITS 

EASY-TO- INSTALL, Hf PERFORMANCE LOW-FREQUENCY ANTENNAS 



Mfd. under 

Tel rex Pat. 

2,576,929 



"Mono" Bands from $23.95-AIsc "Trapped" 2 and 3 Band Kits, 
3, 4 or 5 Band "ConicaMnverted-V" Antennas from $52.95 
3, 4 or 5 Band, 5 to 10 DB— "Empirical— I.V.— Logs"— S.A.S.E. 

TELREX COMMUNICATION ENGINEERING LABORATORIES-ASBURY PARK, N. J, 07712 




FEBRUARY 1968 



23 



James Ashe 
R. D. I 

Freeville, N. Y. 13068 



100 KHZ Thin-line Pulse Generator 



Digital integrated circuits are an entirely 
new kind of electronic component. These 
finished, ready-to-go devices contain com- 
plex transistor circuits in tiny, convenient 
packages. Until recently they were too ex- 
pensive for one-off projects, but a burgeon- 
ing market and competition between manu- 
facturers have brought some prices to the 
dollar apiece level, In fact, very good digital 
IC's are now available on the surplus market 

Perhaps because they are so new, it is 
hard to see applications for digital iCs out- 
side the computer and industrial control 
scene. It takes a little while to adjust mental 
perspective, too, before their input-output 
characteristics begin to seem natural. Yet, 
there are applications for them which are 
not very difficult, For instance, how about a 
frequency standard? 

Ordinary 100-kHz frequency standards are 
usually audible up to a few tens of mega- 
hertz, A good one might be usable at 50 
MHz, The circuit described here uses a dual 
NAND gate to generate a 100 kHz signal 



whose harmonics are usable to 432 MHz or 
higher. And it can be built without benefit 
of special instruments and knowledge. 



The thin line pul: 

One rather surprising result of higher 
mathematics is that all repetitive signals are 
composed of harmonically related sine and 
cosine waves. For example, the familiar 
square wave is composed of a fundamental 
frequency, which sets its basic repetition 
rate, and of odd harmonics only of its funda- 
mental, which contribute to its square cor- 
ners. If the harmonics' amplitude or phase 
relationship is upset, the square wave is dis- 
torted. This feature makes the square wave 
very useful for amplifier testing, but its har- 
monic content is not very good for frequency 
standard applications. 

Now suppose that we start adding up sig- 
nals of F ? 2F, 3F, and so on, phased in so 
that they all reinforce each other once per 
cycle. Let's say thay are all the same ampli- 
tude. What would we get? See Fig. 1A. 






External view of the 100 
Hi thin-line generator. 







mm 








■Qp** 





•^f $ 




24 



73 MAGAZINE 



The five equal amplitude sine waves peak 
simultaneously at the beginning of the fun- 
damental's cycle. Everywhere else, until near 
the end of the cycle, they are more or less 
out of phase. Trying to see what will happen, 
we try adding the first two frequencies. 
Fig, IB, the result, might suggest something 
to a mathematician. 



Zf 



3F 



4F 



5F 




(A) 




(B) 
Fig* I. Five sine waves (A) and the waveform as a 
result of point-by-point addition (B). 

As the number of frequencies is increased, 
their amplitudes tend to average to zero 
everywhere except at the beginning of the 
cycle. Here, they all add up to a short, sharp 
pulse, It follows that a short, repetitive, one- 
sided pulse should contain odd and even 
multiples of the fundamental frequency. 

An ideal thin line pulse has infinite fre- 
quency content.* No real signal could meet 
this spec, but a fast digital IC can produce 
a very workable approximation. Fig. 2 
shows a Tektronix 545A view of the gen- 
erator output and tests with other scopes 
indicate the real pulse has better rise time 
and sharper corners than shown here. 

If this pulse is viewed on a low-perform- 
ance service variety scope, its appearance 
will be greatly changed. There will be an 
apparent loss in amplitude, since the pulse 
occurs and terminates before the slow cir- 
cuitry can properly respond* The apparent 
duration is increased, also because of the 



slower viewing circuitry. And the fast pulse 
may excite circuit resonances, so that the 
thin line pulse appears as a damped oscilla- 
tion. But these problems do not interfere 
with constructing the generator, because 
the very simple NAND gate circuitry con- 
tains no critical elements or adjustments. 

How rt works 

There are four circuit sections, shown in 
Fig, 3. A IGO-kHz crystal-stabilized oscilla- 
tor sets the basic frequency, and a dual 
XAND gate circuit converts the oscillator 
output to a thin line pulse, A 1-Hz astable 
generates the output marking signal. A 6 
volt dc power source is provided by a volt- 
age doubler zener- regulated supply. 

Multivibrator oscillators are not ordinarily 
very stable frequency sources. But if the os- 
cillator is designed to run slightly below 
required frequency, and an appropriate crys- 
tal is connected between transistor base 
terminals, oscillations are stabilized at the 
crystal frequency. 

The crystal does not change the multi- 
vibrator's style of operation, It synchronizes 
the astable to its own frequency, by trigger- 
ing the OFF transistor into conduction short- 
ly before normal RC turn-on. The output 
is a squarish wave with good fall time, but a 
long rise time as shown in Fig. 4A. 

In passing through the first NAND gate 
the pulse is squared up and becomes slightly 
unsymmetricaL See Fig. 4B. A differentiat- 
ing network, C7 and Rll, converts the square 
wave into the pulses shown in Fig, 4C. These 
pulses, applied to the second NAND gate, 
reappear as the thin line pulses shown in 
Fig. 4D. 

Since one CW signal sounds just like an- 
other and there may be several in the vicinity 
of a check point, a marker feature is re- 
quired. This is provided by the 1-Hz astable, 
which paralyzes the second NAND gate part 
of the time. Its base bias resistors are un- 
equal, giving a distinctive duty cycle to the 
output signal, A switch disables the astable 
if a continuous signal is required. Fig. 5 
shows the output when the second astable 
is operating: the output is locked in the up 
condition during half of each 1-Hz astable 
cvcle. 

Sometimes an astable oscillator will refuse 
to start oscillating when it is turned on. It 
does not start because both transistors are 

*Srnith, Applied Mcvthttii&tic$ for Radio and Communi- 
cations Engineer*, Dover Publications, 1961, 



FEBRUARY 1968 



25 



V) 

\- 
_l 

o 

> 



+ 6 

+ £ 





10 MICROSECONDS TO NEXT PULSE 



100 



NANOSECONDS 



200 



Fig. 2* Real circuit output as seen by a Tektronix 
545A oscilloscope. A faster scope shows shorter rise- 
time and sharper corners, 

in saturation, This reduces loop gain so 
that available noise cannot be amplified 
around the loop. It would never start with- 
out some strong, outside interference. 

A pair of diodes, Dl and D2 3 provide a 
reliable remedy. The diodes are arranged 
so that base bias must come from whichever 
collector is at the higher voltage. If both 
transistors are in saturation, their collectors 
are at perhaps 1 volt, which cannot provide 
enough base current to keep the transistors 
in saturation, This contradictory situation 
does not arise in the real circuit which 
starts reliably. 



Additional diodes, D5 through D8, appear 
in the base circuit of the 1-Hz astable. 
These are protective diodes. The collector 
swing at turnoff of about 5 volts is con- 
veyed powerfully to the opposite base 
through the large coupling capacitors C5 
and C6. The reverse B-E breakdown voltage 
of these transistors is not known, so the 
diodes are provided to prevent the turnoff 
voltage exceeding 2 volts or so. 

DC power for the Generator circuitry 
comes from a voltage doubler supply based 
on a low-current filament transformer. Its 
design is conventional, but a large capacitor, 
C12, is provided across its output to mini- 
mize noise on the supply line. The supply 
could be replaced with some batteries, 
shunted by a 50 mF or larger capacitor to 
absorb transients. The original breadboard 
ran very well, powered by four flashlight 
batteries, 

Construction 

The generator is built in a Premier #PMC 



R2 
4.7 k 




R7 
4.7k 

TO G-l 
GATE & 



C4 
[OPTIONAL* 



NOTES 

R3,R5 * COARSE TUNING RESISTORS 

(TO BE SELECTED DURING TUNE-UP) 

09,0-10 ■ SILICON. 25 P!V MJN, 

Ci,C2 ft R4,R6 -MATCHING COMPONENTS 



rn 



TO G-l 
GATE 12 




+ 6 



08 
100 



x 

X 



100 kHi O- 



IHr 



C9 
IOjjF 



♦L' 

X 



8 



DUAL NAWO 
GATE 6-1 



Z 6 II 



C7-A 



RI2 
33 

— VW-Q OUTPUT 



rrr rh 



h 




lOOkKlO 




OUTPUT 



i tfi I 



O 

117 VAC 
Q 



— or ( 




CIO 
SOOyF 



CM 

500 jjF 




era 

SOjiF 



DM 
Z4XL6.2 





ORfENTATIQN 
NOTCH 



O 




o 




Fig. 3. Schematic of the 100 Hi thin-line generator. 



ic PACKAGE 



/ 



26 



73 MAGAZINE 



e 



+ 6 

+4 

+2 






10 



MICROSECONDS 



20 



(A) 



«3 

b 

O 
> 



CO 



+6 










+ 4 ■ 










+2 • 

• 

< 






^j 




3 


10 


20 






MICROSECONDS 








(B) 




■♦■6 






■ 


+4 
4-2 


It 


^ 




T ■- 











to 


— * 
20 






MICROS! 


ICONOS 





to 



3 

> 



+6 
+4 

+2 




10 



MICROSECONDS 



20 



(D) 

Fig. 4* Signals at four critical points in the gener- 
ator, as displayed on a Tektronix 545A oscilloscope. 
They are shown in time coinciSence. 

1008 3x5x7 inch heavy aluminum box. Its 
top cover was refinished in light green enam- 
el, and four % inch grommets in the bottom 
piece serve as protective feet. 

Inside the box, the 6, 3 -volt transformer 
and cheater cord connector are mounted on 
the left-hand wall A pilot lamp, fuse, and 
two switches are mounted on the horizontal 
panel, at the extreme left. This leaves just 
enough open space for the two circuit boards 
which occupy most of the box. Two banana 
jack output connectors are placed on the 
right-hand side, just below the panel 

The circuit boards are cut to 4% x 5 
inches 3 from Vector %2 inch pattern A stock 
and mounted parallel to the panel. The up- 
per board is spaced an inch from the panel, 
and carries both astable oscillator circuits. 
The other board is mounted one half inch 
below, and carries the digital IC and the 



power supply circuitry. Assembled, the two 
boards make a sandwich with wiring sides 
together. 

Both boards are mounted on the same 
four centers. These are through the second 
hole diagonally inward from each comer. 
The 1 inch 6-32 internally threaded spacers 
are modified by adding a short length of 
6-32 threaded shaft to one end of each, sim- 
plifying assembly. 

Component assembly on the boards is 
largely a matter of plugging in Vector T9.4 
lugs. The finished product looks much bet- 
ter if some thought is given to facing the 
lugs in one of two directions, Mounting and 
transistor holes should be drilled and reamed 
to size before installing lugs, 

The general arrangement puts all wiring 
on one side of the board and practically 
all components on the other side. This ap- 
proach seems a little inflexible but is straight- 
forward and looks good. 

Possible board orientation problems may 
be overcome by working out a handling and 
wiring procedure that doesn't require con- 
stant reference to actual components, A good 
approach assumes that the board is only 
turned over an imaginary hinge at its 
bottom edge, so that top down when one 
side is up becomes bottom up when the 
other side is down. This preserves left-right 
relationships* Another useful convention is 
that all supply wiring goes to left-hand end 
of components. 

Wiring is carried out one network (plus 
supply lines; ground lines; interstage lines, 
etc) at a time, with prearranged color 
coding. Bare wire goes for short runs and 
where there is no chance of a short. Solder 
each lug when convenient, #22 solid wire 
fits the T9.4 lugs well, but flexible stranded 
wire is used for the four iines from one 
board to the other. 

Transistors precede other components in- 
to the board, because they are convenient 
position markers. They are placed in their 



2ND NAND GATE 
HARD ON 



GATE TRANSMITS 
SfGNAL 



to 

5 



+ 6 

+4 

+2 






O 



0.5 



SECONDS 



1.0 



Fig. 5. The second NAND gate locks in its up posi- 
tion part ot the time to produce an intermittent 
output. 



FEBRUARY 1968 



27 




Inside the assembled thin-line generator showing the 
component side of the power supply and IC board, 

mounting holes in the board from the com- 
ponent side, and their leads brought to the 
T9.4 lugs. 

Then the other components are mounted 
on the boards, 

product. Diode and electrolytic capacitor 
mounting polarity should be double checked. 
The T9.4 lugs may need a little bending 
before they will take a good grip on the 
components, but no component soldering is 
done until everything is installed. 

Trimmer capacitor C3 is mounted on its 
tabs just under the top panel. Then a small 
screwdriver access hole is drilled over it in 
the panel, before painting, for vernier fre- 
quency adjustment after final assembly. 

Certain components are matched before 
installation, An ohmmeter and a capacitor 
checker will do a satisfactory job of select- 
ing CI and C2, and R4 and R6 ? for equal 
values. These components are chosen alike 
for best symmetry of the 100-kHz oscillator 
operation. It might be good planning to 
leave these components unsoldered until tun- 
ing is completed, but everything else can be 
soldered to the board at this point. Note 
that the R3 and R5 sites do not get resistors 
until later. 

Two optional capacitor sites are included, 
These are for C4, an additional and prob- 
ably unnecessary padder across the crystal; 
and C7A, which can be added to increase 
the width of the thin line pulse. 

Apparently, the digital IC comes in a 
specially designed package for testing before 
use. To mount the IC, solder a % inch 
piece of #22 wire in each of the T9.4 
ugs carrying supply and signal voltages to 



the IC. Place the IC between the two rows 
of lugs, bend the wires against the proper 
terminals, and solder. No other mounting is 
required. 

The original breadboard showed a lot of 
transient noise in its supply circuit. This 
originated from the IC, which was trying 
to get big chunks of current to manufacture 
pulses. Since the IC cannot deliver frequen- 
cies not available from the supply lines* very 
careful bypassing is indicated. 

High-frequency bypassing consists of C9, 
a .01 /*F disc ceramic capacitor across the 
IC supply terminals on the wiring side of 
the board, and CIO, a 100 picofarad capaci- 
tor soldered directly between supply termin- 
als on the IC. The capacitor leads are pro- 
vided with spaghetti insulation and placed for 
minimum open space between the capacitor 
leads and the IC's supply leads. 

Testing before final assembly is very easy, 
because the odd appearing board layouts 
go together giving a structure that opens out 
like a book. The hinge is the four leads 
between boards. Leave transformer leads long, 
so that the circuit may be tested well free 
of its cabinet 

The upper half of the Premier box is pre- 
pared by a powerful cleaner which removes 
its original paint. After thorough removal 
of the cleaner, the metal is roughened with 
wet sandpaper, rinsed in vinegar solution 
and then clear water, leaving a very good 
surface that does not require priming for 
excellent paint adhesion. Watch out for 
greasy fingerprints, 

Rustoleum #868 Green applied from a 
convenient spray can gives a fine finish. 



•r 

::• 



.:;. 



'■ :■ 



■■■& 






.. 




View of the component side of the astable oscilla 
tors board. 



28 



73 MAGAZINE 









■^ 


^TOP 

j 

1 


PANEL 


T 
'i 








- COMPONENT STOE 
OF ASTABLE BOARD 


^* 


*~~ 


c j 




3/32" T~ 

xrt 




J] 




**c 


OF 


^ , . 


n^^"^^^^^i 




COMPONENT SIDE 
4 IC BOARD 


SUPPLY 


THREADED STUD 
INSIDE 



Fig. 6. Mounting dimensions and spacer assembly 
diagram. 

Follow instructions on the can. After drying, 
the fresh, clean enamel will take water- 
proof India ink, applied with a Leroy draft- 
ing pen. When the ink is thoroughly dry, a 
final coat of Rustoleum #717 Clear finishes 
the job. The enamel is soft at first, but 
hardens into a coat durable in normal lab 
use. 

Table of special parts 

Crystal: 100 kHz parallel resonant 32 pF. shunt ca- 
pacitance normally designed quartz crystal. 

The following parts were obtained from Solid State 
Sales, P. O. Box 74. Somerville, Mass. 02143. 
Tl & T2: 2N2060 type dual NPN transistor 
Dl, 02, 03, D4: fast point-contact Germanium 
diodes coded I N59 

D5, D6, D7, D8: fast point-contact Silicon di- 
odes marked S284GM 

©I: surplus digital integrated circuit 

Solid State Sales type Gl. (comes with data 
sheet) 

Tuning up 

The generator should be zeroed to fre- 
quency before installation in its case. This 
is a two-step process. First, the 100-kHz 
astable base resistances are adjusted by 
choosing resistors for R3 and R5 to bring 
the oscillator frequency within trimmer range 
of 100 kHz, perhaps a few hundred cycles 
high at 15 MHz. Then the trimming capaci- 
tor brings the frequency to accurate coinci- 
dence with WWV. 

To roughly zero the generator, set the 
trimmer capacitor, C3, at minimum capaci- 
tance. Identify WWV on a short-wave re- 
ceiver, and tune around a bit to familiarize 
yourself with what's happening in the vicin- 
ity. It would be nice if things are fairly 



Then put 4.7k resistors into the astable 
board at the R3 and R5 sites, turn on the 
generator, and look around for the signal. 
Depending upon actual values of CI and 
C2, the signal may be on either side of 
WWV but is likely' to be on the high side. 



If so, try again with resistors one size larger, 
which will lower the frequency. You should 
shortly find resistors that bring the fre- 
quency near enough to WWV for final zero- 
ing with the capacitor. Verify tuning range 
on both sides of WWV. 

Correct values for R3 and R5 may be 
approximated very quickly if a good trig- 
gered scope is available. Try selecting re- 
sistors for a period of 11.4 microseconds with 
the crystal removed. 



Using the thin line generator 

A breadboard test showed that (as might 
have been expected) there should be some 
way to distinguish generator signals from 
other CW signals. The continuous /intermit- 
tent feature provides the marking, and once 
the correct signal is located the generator 
can be switched to "continuous" for accurate 
work. 

At low frequencies, the generator output 
and behavior resembles a conventional 100- 
kHz standard. The signal simply is not as 
strong. A greater difference appears at 
higher frequencies: the original model yields 
an audible beat note at 80-MHz from a diode 
mixer through an inexpensive audio ampli- 
fier. And another test shows a usable signal 
at 432 MHz: the 4,320th harmonic. 

Some connection to the receiver or other 
detector is required. This is a natural con- 
sequence of a circuit design that puts the 
signal where it belongs, rather than spray- 
ing it all over the lab. A few picofarads 
coupling capacitance is sufficient at all fre- 
quencies. 

Perhaps this circuit can be used for pur- 
poses other than a frequency standard. Its 
moderate amplitude but wideband output 
should be ideal for detecting changes in 
receiver sensitivity over a broad tuning 
range. In fact, with a little decoupling of 
the input leads and provision of a coax out- 
put connector the generator should do well 
as a stable, reliable small-signal source. A 
piece of adjustable waveguide-below-cutoff 
would make an excellent attenuator for 
work not requiring exact measurements. An- 
other thought that occurs is possible further 
development by provision of some arrange- 
ment for detecting which harmonic is actual- 
ly being heard. 

. . . W2DXH 



FEBRUARY 1968 



2? 



Eugene Fleming W0HMK 

328 Gunnison Ave. 

Grand Junction, Colo. 81501 



The Nurture and Care of a Junk Box 



The idea of "the junk box" has been 
laughed at, slandered and otherwise malign- 
ed during the past couple of years . This 
fun-making and detraction has gone on 
both in the magazines and in QSOs. May- 
be it is time to take a second, and a close, 
look at this institution which is as much a 
part of ham radio as are DX contests and 
YL chasing. 

Why has there been so much disparage- 
ment? My own idea is that writers for ham 
publications have assumed (usually errone- 
ously) that readers had junk boxes as ex- 
tensive as, and identical to, their own. When 
readers figured out the cost of what they 
had to buy to complete the particular pro- 
ject under consideration, they often gave 
up rather than strain their budget. How- 
ever, if those readers had been making a 
systematic effort to grow themselves a good 
supply of used parts, they might have built 
the gismo for less than it cost the author. 

Extensive parts collections don't just hap- 
pen. They are grown more or less inten- 
tionally. Here are a few hints on the accu- 
mulation of parts and how to handle them 
after you get them- My XYL says this is the 
only subject on which I am an expert, so 



maybe others will find the techniques use- 
ful. 

1. Let it be known among yout friends 
and acquaintances that you are interested 
in electronics. Forthright announcement is 
sometimes appropriate, but demonstrations 
are better for they make a more perma- 
nent impression. Display of some electronic 
gadget or your call letters can be used to 
advantage. Gadgets give you the best open- 
ings for conversation on the subject. "Com- 
mercial killer" for a TV set or a neon 
bulb flasher are examples. When it is learn- 
ed that "he built it himself", not a few 
friends and relatives will say, "Maybe he 
can fix that old radio in our attic, and 
if not, maybe he can use the parts/* Need- 
less to say, the radio is beyond repair 99% 
of the time. When you are offered pay for 
a small favor ask if there is an old radio 
or record player you might have. Some- 
times these are repairable and can be used 
for swapping material. 

2- The offer of old electronic gear brings 
us to the second point: Never refuse an 
offer of anything. Don't refuse even if you 
are certain beyond any doubt that you can't 
even get the beast into your basement or 




30 



73 MAGAZINE 



use any part of it The friend making the 
offer sees himself as doing you a favor by 
offering it and at the same time is getting 
his attic cleaned. And who knows, you might 
find just what you need in it for a pro- 
ject 5 years later- Such an unlikely pro- 
spect as a broken egg beater has been turn- 
ed into strap to hold a tubular electrolytic 
in place, and the wood from the handle 
used for insulating spacers! 

3. Approach likely sources of used equip- 
ment which can be stripped. Repair shops 
for TV and radio, 2 way radio, and sal- 
vage businesses are good prospects. One 
fellow got the privilege of hauling away 
the trash from a TV service shop. No one 
specified that it was all to go to the dump, 
and you can bet it didn't. He netted a 
couple of chasis per month in return for an 
hour's work, and supplied the local demand 
for power transformers. He could have de- 
veloped a tremendous stock of resistors if 
he had wanted to. 

4. If absolutely necessary, buy equip- 
ment that has many usable parts. The best 
example of this is the plug-in units from 
computers that several of the well known 
mail order houses currently list in their 
regular catalogs. These have many parts 
useful in general construction projects such 
as standard value resistors, terminal strips, 
etc, One was recently obtained which had 
an even one hundred diodes plus almost as 
many resistors for a single dollar bill 
Some military surplus is worth purchasing 
if the price is very low. Auto junk yards 
will often sell non-operating radios for a 
buck or so, The transistors or tubes can be 
worth much more than that, and if the 
speaker is thrown in, that makes a real 
bargain. Some of the best hunting can be 
done at auctions, both radio club and com- 
mercial Unlike taking gifts mentioned 
above, be discriminating in what you buy. 
It is not a bargain if you have no use for 
the parts, 

5. Carefully choose assortments to fill in 
the gaps in your parts supply while you 
continue growing your own collection. These 
can often be bought at half what they 
would cost if purchased individually. The 
more precisely you know what is in the as- 
sortment the more it will cost however. Ex- 
perience shows that grab bags of a specific 
part such as capacitors or knobs from well 
known mail order houses are well worth 
the money. This is not always true of as- 



sortments from smaller places* For example, 
a pound of resistors from a relatively ob- 
scure supplier contained a half pound of 
22,000 ohm 2 watters. That value is great, 
but who needs 75 of them? 

6. Avoid the "5 pound surprise box**- 
The surprise is seldom a pleasant one. These 
are usually made up from odds and ends 
which can not be sold otherwise. Even so, 
some guys will gamble. One such assort- 
ment contained 2 pounds of packing! 

7. Develop a working swap arrangement 
with other fellows in your area who have 
a junk box. This can effectively multiply 
the stock of parts you have to choose from. 
Be sure to test the parts before the deal 
is final. This can save a mutually benefi- 
cial friendship. 

A place you are likely to find people in- 
terested in swapping is the local ham club. 
Fellows who attend are the ones most likelv 
to be active in building. Putting out feel- 
ers on local VHF nets is another way to es- 
tablish contact between builders, A some- 
what unexpected source of possible fellow 
hohhiests is the names found on the book 
cards of people who have recently checked 
out electronic books from the library. 

Now that you have accumulated the 
equipment with all those useful components 
in it, let's don't chuck it under the work- 
bench for future reference. Trying to lo- 
cate a specific relay or capacitor to fit the 
specs of that article in the latest issue of 
73 can be time consuming as well as frus- 
trating. Two words that are a must in the 
nurture of a junk box are organize and 
test. 

To organize those goodies, you have to 
get them off the original chasis. Hand tools, 
a soldering gun and soldering aid are es- 
sential. Unsolder parts whenever possible 
rather than clipping leads* This is more 
time consuming, but will save later frus- 
tration when looking for a component with 
leads long enough to reach without having 
to splice. Often as much as % inch of wire 
is wrapped around the terminals. Such items 
as sockets, relays, and terminal strips, are 
then ready to use without requiring clean- 
ing. When there is a long evening while 
wating for that next magazine, get out the 
tools and start stripping. 

No sensible person is going to dump all 
those parts into one big box. Everything 
from shoe boxes to olive jars has been sug- 
gested for separating and storing the parts. 



FEBRUARY 1968 



31 



M- 



The type container is not as important as 
having some kind of system. If you can 
pry loose some savings stamps from the 
XYX/s horde, you might get some of the 
plastic drawer cabinets which are ideal for 
smaller components. 

Don't stop by just putting the parts into 
the boxes or you will end up looking thru 
nineteen shoe boxes to find which one the 
tube sockets are in. A child's wax crayon 
or a china marking pencil is a cheap, quick, 
and easy labeling instrument. 

Then we come to the testing. Who wants 
a basement full of parts that he is not sure 
are usable? Most experimenters have an ohm 
meter that will take care of the resistors 
and inductors. Radio clubs often have test 
equipment they will loan or rent to mem- 
bers. Many amateurs will test components 
gratis for a fellow hobbyist if they have the 
equipment to do so, or have access to it. 
Drugstore tube testers tend to develop bad 
socket connections. Since they are not 
checked very often, they may indicate a 
fault where there is none. If you must use 



them, be very cautious in disposing of **bad" 
tubes. The bases from octal tubes make 
excellent cable terminals and don't require 
expensive sockets either. 

This isn't the place to get into testing pro- 
cedures for they are well covered in other 
articles. It might be a good investment of 
your time and horde of parts to use some 
of them in building test instruments for 
finding the condition of parts you may 
acquire in the future. 

A word of caution is in order. Do not 
be in too big a hurry to wreck out every- 
thing you get your hands on. Such things 
as audio amplifiers can be used around the 
shack for a variety of purposes like con- 
version to an intercom or a modulator. 
Radios, especially transistor radios, as well 
as record players and intercoms can be pro- 
fitably bartered or sold. 

Now you can compete with the best of 
the scavengers. So start saving your pen- 
nies. No, not for snapping up the bargains. 
You're going to need a bigger shack to 
store all those junk boxes! 

. . , W0HMK 



A word to radio clubs 

Fellows, is your club doing the best job it 
can to encourage new amateurs in your com- 
munity? Rate your club 

1- Does your club have an organized pro- 
gram to invite CB'ers to come to club meet- 
ings and get acquainted? 

2. Does your club roll out the red carpet for 
newcomers? Are thev introduced around? 
Do you have a committee whose responsi- 
bility it is to see that these fellows are made 
welcome and who answer their questions for 
them? 

3. Do you have a short technical session be- 
fore or as part of each club meeting? Is this 
session run by someone who is a good teacher 
and knows his stuff? 

4. Do you have a code practice class run by 
your club? 

5. Does everyone in your club feel wanted 
and welcome or is there a small clique trying 
to keep out the Novices and unlicensed fel- 
lows? 

6. Do long business meetings make your 
club dull for newcomers? 

7. Do you have a refreshment session at the 
end of a meeting to allow everyone a chance 
to chew the rag? 



8. Do members with technical questions and 
problems have anyone they can call or turn 
to for help? 

9. Does your club help members to put up 
beams, towers, and other operations where 
a group is needed? 

10. Does your club have a local VHF chan- 
nel where members can call in for assistance 
or information? 

Count ten points for each unequivical yes, 
less for ves, buts. 

The newcomer to amateur radio has a hard 
row to hoe and it is up to the rest of us to 
make this path as simple to follow as pos- 
sible. The Novice license is easy to get, but 
right at this point the Novice needs help 
badly if he is not going to waste a lot of 
money buying equipment which is going to 
frustrate him. The Novice bands are crowded 
and are no place for junky gear. You need 
good receivers and rigs to get any enjoy- 
ment out of these busy bands, A poor re- 
ceiver will end one contact after another due 
to QRM + This can completely discourage just 
about anyone. It is no wonder we lose so 
many Novices each year. The wonder is that 
as many get through this baptism of QRM 
as do. 

.. . W2NSD/1 



32 



73 MAGAZINE 



Can 



swing 



beam? 

Here's the best 
solution 
under the sun. 



If you haven't the room or the cash to swing a beam 
(or if your wife doesn't appreciate the beam's beauty), 
how can you stii! get on the air? With a Hy-Gain 
14AVQ, the most popular vertical under the sun. And 
what about versatility? A Hy-Gain 14AVQ goes along 
on virtually every "DX-pedition/' 

Hy-Gain 14AVQ is constructed of 
high-grade heat-treated aluminum 
and uses high impact polystyrene. 
No need to worry about rust and 
deterioration common in others 
using cadmium plated steel. 



This vertical develops on extremely 
low-angle radiation pattern that in- 
sures a powerful signal for short 
hauls and DX. You get low VSWR 
across all bands plus the ability to 
adjust (and easily re-adjust) for 
peak performance at any specific 
frequency. "Hy-Q" low loss traps 
are individually precision tuned to 
frequency giving a true resonance 
on each band. It's the only trap 
vertical at DC ground, resulting in 
less static and lightning problems. 

If you already have a Hy-Gain 
14AVQ r why not buy another one 
and phase 'em? When you do, 
you'll get the signal directivity of 
a beam without a tower or rotor 
and escape the worry of wind and 
ice damage. 

Buy your 14AVQ from one of the 
best distributors under the sun — 
those who stock Hy-Gain. Hy-Gain 
Electronics Corporation, N.E. High- 
way 6, Lincoln! Nebraska 68501, 
Dept AC-12. 



mg 









HY-GAIN ANTENNAS, FOR THE MOST POWERFUL SIGNAL UNDER THE SUN 



Dr, Louis E. Persons W4PJG 

P.O. Box 1647 

Ft, Myers, Fla* 33902 



How to Plan Your Own DXpedition 



A DXpedition to the Cayman Islands by K4CAH, 
W4KET, W4PJG, and WA4WIP 



First look for some rare or semi-rare coun- 
try with an exotic call that is easily accessible. 
We looked in the Caribbean area, Navassa 
was out of the picture, the VP2's were avail- 
able, but had really been worked over during 
the past year. We tried to obtain a VP7 
license but were unsuccessful. So Grand 
Cayman Island was what we were looking 
for. A new exotic prefix of ZF1 was recently 
assigned, having been changed from VPS. 
This, in fact, caused us some trouble. Many 
stations not finding ZF listed in their "late" 
1950 call book, openly accused us on the air 
of being pirates. 

Nice hotels on beautiful beaches were 
available, that would cooperate with a bunch 
of hams and their strange array of equip- 
ment. And most of all, after completing an 
application form along with $14 U.S. funds, 
two months of waiting, and some help by 
the country's only active permanent amateur, 
Frank Scotland, ZF1GC, the call of ZF1EP 
was issued. 

So! We had our country and our license. 
Let's throw our toothbrush in our pocket 
(Ernie, K4CAH being a dentist insisted on 
this) and put our sunglasses on for the 
Caribbean sun (Lou, W4PJG, an optometrist, 




ZFIEP DXpedition. QSL card. The shack in the 
background shows the hardships the boys had to 
put up with. 



demanded this) and be off— we thought. We 
soon found that there was just a little more 
to planning the trip. Questions, such as the 
following had to be answered: what equip- 
ment to take, linears or not, what type of 
antennas, what to support the antennas, was 
there commercial power available, how many 
stations to operate, how long a power cable 
to take, how much coax, ground rods, spare 
tubes and parts, test meters, does the plane 
fly into the island on the day we must go, 
do we need passports, innoculations, etc. 
etc. 

It was immediately seen that it would 
take several weeks to answer all of these 
questions, But we were determined to plan 
every detail in advance, even to assembling 
all gear and timing how long it would take 
to set up two stations with the color coded 
antennas, and be on the air. This advance 
assembly and trial paid off in an operation 
with no problems at all— a rare experience- 
So we now have the country and the 
license along with some basic travel informa- 
tion, we knew we could get there. 

In our case, Grand Cayman, British West 
Indies, is located 150 miles south of Cuba, 
180 miles northwest of Jamaica, and about 
600 miles from our home in Florida. It is 
easily reached by direct flights from Miami 
three days a week by LACS A Airlines. 
LACSA is a Costa Rican airline that serves 
that part of the Caribbean. The food and 
drinks served on this airline is superior to 
any we have ever experienced. 

A U. S. passport is a must for any serious 
U.S. DXpeditioner. A passport is obtained by 
taking your birth certificate and two recent 
"passport size" photographs to your county 
clerk's office along with $9.00. It usually 
takes two weeks for it to be mailed to you. 
A recent small-pox vaccination form, verified 
by U. S. Health Dept, is also required to re- 



34 



73 MAGAZINE 




Our shopping bags each contained a TR-4 or power 
supply. All other gear and antenna in the long pack- 
age. 

enter the U, S, after visiting the Cayman 
Islands and many other areas. It is of course 
wise to keep -up other appropriate innocula- 
tions such as tetanus, typhoid, etc. 

We found by inquiring through the tourist 
bureau of Grand Cayman that several excel- 
lent small hotels were available on the island. 
The next step was to contact a hotel there 
and explain what we wanted to do as to 
erecting antennas etc., and make the reserva- 
tions. Our choice was the Beach Club Colony 
Hotel which proved to be in excellent choice 
in accommodations, cooperation and fine 
meals. We then made our airline reserva- 
tions. We were told that 24 hour commercial 
power was available on the Beach Club Hotel 
part of the island. This was a relief to find 
that we did not have to take, or to arrange 
for, generating equipment and gas. It re- 
mained to be seen however, that the voltage 
never did exceed 100 volts and most of the 
time was around 95. An auto transformer 
would have helped. Next on our list was the 
equipment and antennas. Since commercial 
power was available, we would only be 
limited in equipment by the amount of ex- 
cess baggage charges we wished to pay on 
the airline. We were allowed 60 pounds 
apiece or with four of us going, a total of 240 
pounds of baggage. If we exceeded this the 
cost would be 25 cents per pound. 

Negotiations were made with the R. L. 
Drake Company to supply us with two com- 
plete stations consisting of the DRAKE TR-4 
Transceiver and the RV-4 Remote VFO with 
the power supplies, This is truly the ideal 
DX rig. The remote VFO enables one to 
work different frequencies, with the choice 
of transmit or receive on either frequency 
at the flip of a switch. The TR-4 runs 300 
watts PEP which we felt was ample power 
without paying the excess baggage cost 



which would be necessary if we took linears 
for higher power. More on this power factor 
later. 

Probably the biggest decision to make was 
on the type of antennas to take with us, 
Again we wished to keep the weight down 
and this time also the size of the packages. 
We, of course, wanted the most gain possible 
for the least size. The discussion of which 
was best as far as weight, size, and efficiency 
was whether it would be better to take low 
power with a high gain antenna or high 
power with a low gain antenna, assuming 
that we did not want to take both the linear 
and the beam antenna. The decision as to 
taking the beam really also depends on what 
is going to be taken to support the beam. 
Then the question of a rotator came into the 
picture, Gus, Don, and others have shown 
that the easiest antenna to carry is the HY- 
GAIN Vertical variety, As we planned to 
operate all bands 80 thru 10 the HI-GAIN 
18AVQ vertical was at once chosen for 
one antenna as it covers all these bands. 
The HY-GAIN TH-3 MK11 three element 
10, 15, 20 meter beam was at last chosen 
for the other antenna. It was at first thought 
that the regular TV type three section 30 foot 
pushup masts with guys would be taken to 
support the beam, but it was later decided 
to take the type mast with 6 pieces of 5 
foot interlocking steel tubing. The cost, un- 
assembled length, and weight being less 
on the latter. The mast is a dispensable item 
for the return trip to save weight, if you 
like. Ample wire was also taken to make up 
coax fed dipoles if the need arose, and it 
did, due to the need to operate one rig on the 
18AVQ on 40, and a dipole for the other 
rig on 80. Three lengths of coax were taken 
for each antenna, along with the necessary 
insulators and guy wire. 

With all equipment on hand both stations 
were set up at the home QTH of Ernie, 
K4CAH, The antennas were carefully meas- 
ured and assembled. As each section was 
tightened, the joint was sprayed with a can 
of spray paint so it would not be necessary to 
ever measure again on reassemble, just line 
up the paint lines. The sections of the vertical 
were numbered with a marking pen starting 
with number one at the base. In the case of 
the beam, each element was sprayed a dif- 
ferent color on the joints for easy recognition 
of elements- A word to the wise here— DO 
NOT tighten down on the compression 
clamps too much if you ever expect to take 



FEBRUARY 1968 



35 



■M 




A Beam is a lot more trouble to erect and keep up, 
but the extra gain may be worth the effort, 

apart and reassemble the antennas again with 
ease* Just tighten enough to hold. Once the 
HY-GAIN 18AVQ vertical has been pie- 
assembled in this manner, it can be unpacked 
and on the air in ten minutes. Other miscel- 
laneous equipment included two micro- 
phones for VOX or push to talk, keys, 
W4KET took his TO-Keyer, spare tubes, 
diodes for the power supplies, fuses (which 
we almost forgot), small multi-test meter, 
headphones, ground rods, ground wire, ac 
extension cords, heavy hammer to drive 
ground rods, and other items for personal 
comfort such as insect repellent and sun tan 
lotions. 

It is interesting to note that tne above 
equipment weighed 120 pounds and the 
package of antennas, ground rods, mast and 
coax weighed 117 pounds. It is also interest- 
ing to remember that airlines very carefully 
weigh all baggage and charge accordingly 
for any excess weight, but many times they 
do not take the time to weigh the contents 
of shopping bags or hand-held articles if 
these are not spotted by them until you are 
going through the gate to board the plane. 
Needless to say, the four of us were carry- 
ing "small" shopping bags with a Drake 
TR-4, RV-4, or power supply in each as we 
boarded the plane* As our checked baggage 
was "light" we paid no extra charges. 

The flight from Miami was a pleasant one 
passing directly over Havana and the Bay of 
Pigs, Cuba, We were content to just observe 
the country side rather than attempt a 
DXpedition to that country. 

We were met at the Grand Cayman Air- 
port by Frank Scotland, ZF1GC, who stood 
by patiently as we made sure that our an- 



tennas were unloaded from the plane and as 
we passed through customs with no prob- 
lems. We later visited Frank's shack where 
he owns and operates the power plant for the 
other end of the island from where we were 
staying. Frank may be found every night on 
3915 SSB, and occasionally on 15 and 20 
where he gives many their first ZF. Frank 
gave a helping hand many times during our 
stay. He was typical of the people on the 
island— the most friendly people in the world. 
The language is entirely English but with a 
slightly different accent from our own. 

Our vertical was set up outside our cottage 
on the white sand of the beach only a short 
distance from the beautiful green-blue Carib- 
bean water. Dick, WA4WIP, insisted on 
keeping the ground system around the base 
of the 18AVQ vertical well watered down 
with the salt water for a good ground. Ap- 
parently it paid off too. Our first contact 
from ZF1EP was on 15 meters to W8GCE 
followed by K7AQB, K8VCT, W8HIZ, 
K9URA, W5HWB all with 59 reports. On 
20 meters the first QSO was with W4NPT, 
followed by W1BA, G3LGW, WA3EEK/3, 
W4NJF, WA1FOJ, all 59 reports. So we 
were "getting out". 

Some interesting DX worked the first day 
on CW was YU1EXY, UB5KAA, LZ1KPG, 
SP8AJT, VK4AY, OK3UL, HA3GF, QK1HA. 




A pre-marked I8AVQ vertical can be unpacked and 
on the air in ten minutes. 



36 



73 MAGAZINE 



We were pleasantly surprised at the con- 
tinuous "pile-up* ? on us during our 4 day 
stay on the island. We worked 5000 stations 
during our stay and we were well initiated 
into rapid operating techniques. During some 
one-hour operating stretches, over 165 QSO's 
were made, at times, one contact every 17 
seconds, Ten meter pile-ups were the heaviest 
of all! The speed of operating never seemed 
to depend on the operator but rather who 
he was working and the conditions. The 
courtesy of all of the hams was really great. 
If we heard a weak station and had only 
one or two letters of his call the rest of the 
pile-up would stand by when asked. We 
were, of course, interested in making a 
fairly good score in the CQ WW DX Phone 
contest during our stay as well as giving 
many a "new country". 

It was late at night, when conditions 
were poor, that we wished for a linear to 
compete with the South American stations 
with the higher power and a better multiplier 
advantage in the contest scoring. Some of 
the late night DX we did work on 40 SSB 
was VQ9AA/D Don, CT2YA, UA9DT, 
Y09CN, and others. Our power output was 
slightly reduced at night due to the line 
voltage dropping to as low as 80 volts, but 
the Drake TR-4s continued to perform even 
though the power supplies did get a little 
warm. The results with the vertical were 
really amazing, at times tests were made in 
which it equalled the signal of the 3 element 
beam. It is difficult to compare two antennas 
unless they are both operating under op- 
timum similar conditions. The vertical was 
used with an excellent ground system out 
in the clear on the wet salty beach. The 
height of the beam was limited and close to 
the buildings. But these were typical condi- 
tions. If you compare the trouble of getting 
a 3 element beam up in the air, rotating it, 
and keeping it up in the air to the ease of 
erecting the vertical you will pick the vertical 
every time. But then again, how about that 
extra gain of the beam under poor conditions? 
If you are activating a rare country, the rest 
of the world will look for your signal, weak 
or strong. But if you are also interested in 
scoring in a contest, the big signal helps, 
Sunday afternoon came too quickly for us as 
we had to shut the rigs down to catch our 
return plane or else remain on the island 4 
extra days to wait for the next plane. We had 
to lose 5 hours of "prime" operating time in 
the contest because of this, or as Dick, 



• • 



WA4WIP put it, lose 600 QSO's . . . 

Upon arriving back home we found the 
second phase of a DXpedition, the QSLing 
with 200 QSI/s the first day, The mail 
brought several dozen a day for the first 
month. Now several months later we are still 
receiving one or two a day. All of those who 
sent a Self- Addr essed-Stamped-Envelope 
along with their card were answered as soon 
as received after the cards were printed. 
Those who did not send a SASE, well, lots 
of luck, don t be in any hurry for your 
ZF1EP QSL as they will go by the QSL 
Bureaus. To those who think DXpeditions 
make money from all of the contributions 
sent with the QSL, forget it. Out of the first 
1000 cards received, the contributions totaled 
$10,00. To those 1% we send our sincere 
thanks as it did help pay for the QSL cards. 

In conclusion, a well planned DXpedition, 
with good equipment, can be a very enjoy- 
able experience. This group is already plan- 
ning for another trip to another country in 
the next few months , We hope it might be 
a "new one" for you. So that others might 
get the DXpedition "bug" and activate coun- 
tries that we need, we dedicate this article. 

. P . W4PJG 



USED MODEL 501 TV CAMERAS 






: v :* • 






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waaia^stt 



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$160.00 FOB Mollis 

Each month we have a limited number of 
used TV cameras which we make available to 
hams at greatly reduced prices. These cameras 
were rented out for temporary surveillance 
jobs on construction sites, county fairs, con- 
ventions, etc. All have been checked out and 
are guaranteed for 90 days. Complete with 
vidicon and lens. 



Used Model 501 sale priced 
$160.00 FOB Hollis 

Don't delay. Only a few used cameras are 
available each month. For specifications send 
for our illustrated catalog. 



VANGUARD LABS 

Dept. H, 196-23 Jamaica Ave., Mollis, N.Y. 11423 



FEBRUARY 1968 



37 



Ralph Steinberg K6SKX 

I 10 Argonne Ave. 

Long Beach, Calif. 90803 



How is your Club Paper? 

Good or Bad? 



There are two categories in which papers 
can be classified. Either they are good or 
bad. Bad papers have no business to be 
published as they serve no definite purpose, 
If your club paper depends on gossip, bits 
of wit or other nonsense to fill space, your 
club would be better off ceasing publication. 

The reason for having a good paper is 
to furnish the membership informative news, 
technical information, projects and activities 
so that it can be a good communication link 
for the club membership. Very frequently 
papers of this type help to interest new 
members for your club. 

Club papers should be planned like a good 
magazine or newspaper. It must have a set 
format, good composition, interesting ma- 
terial, appeal and appearance. Many editors 
of amateur radio club papers follow such 
planning and turn out excellent papers. 
These editors lay the ground work of their 
next edition at least two weeks or more 
ahead of publications. This gives them plenty 
of time to turn out a paper which is interest- 
ing and a credit to their club. There is 
plenty of material that an editor can have 
ready ahead pf "deadline" so that he will 
not be pinched for time when publication 
date arrives. 

Formats pan be a credit to a publication 
and can be the difference between a success- 
ful publication or one on the skids. Many 
ideas can be checked by reviewing some of 
the national radio and electronics publica- 
tions and 73 Magazine is one of them. 
Formats by these publication editors are 
well planned and if used by radio club edi- 
itors it will contribute interest and reader 
approval by your club membership. Formats 
need imagination and once you find one, 
stick to it. 

Composition and material are two essen- 
tial items to be considered with care. Layout 
of material should not be done in a hap- 
hazard way. Each item of interest should be 
in its proper place. For example, news of 



current interest about your club members 
should be front page copy, Following pages 
can have announcements of future programs, 
new F.C.C, regulations, biography of your 
next guest speaker, editorials, swap lists, auc- 
tions and a technical corner. Each column 
should have a headline to set it apart from 
the one preceding. 

Attractive mastheads are a must. This sets 
your paper apart from the "run of the mill" 
publications. Again be original with your 
ideas, don't copy others. If some member 
of your club does art work, assign him to 
the task of designing the masthead. A favor- 
able idea would be to have a contest and to 
the member turning in the best design, a 
prize could be awarded. A master stencil 
could be made of the masthead and used 
indefinitely. Using a separate color for the 
masthead adds more zest and imagination 
here can go the limit. 

The printing of a paper has a choice of 
process. It can be mimeograph, hekto graph, 
offset or letterpress. Using a mimeograph or 
hektograph process is the cheapest Many 
clubs use either of these and have their 
own machines. In commercial printing, offset 
is the cheapest; although letter press costs 
more but has the quality. Letter press is 
processed by linotype or by hand and, due 
to labor cost, it is more expensive. Pictures 
can be reproduced with letter press with ex- 
cellent results, should you feature them in 
your club paper. The process for offset print- 
ing is by photographing copy of the club 
paper. It is used by many clubs who wish 
that professional look; Commercial printing 
should be given consideration as it adds pres- 
tige and in the long run, cheaper than "do-it- 
yourself" printing. 

How can the cost of the printing be 
raised? There are two angles to consider. 
First ... is to increase the membership dues 
to pay for the cost of printing and the second 
is to have advertisers take space in your 
paper. This would take care of the added 



38 



73 MAGAZINE 



expense of commercial printing. Your mem- 
bers can serve as advertising salesmen and 
a prize can be awarded to the member 
bringing in the most advertising. Who can be 
the advertisers? There is no limit to who is a 
good prospect for advertising. Local amateur 
radio supply stores, surplus stores, drive-ins, 
drug stores and many more are good pros- 
pects and will advertise for the good will it 
creates. 

Rates for advertising has to be judged by 
the expense of printing and mailing your 
paper and the amount of circulation your 
paper has. A typical budget for figuring your 
cost and profit is hard to establish as in some 
sections of the country printing costs are 
either higher or lower than in your area. 
As most radio clubs are non-profit organiza- 
tions, it would be wise to break even. If you 
have a profit there is usually a tax bite to 
even things out 

The editorial staff of a paper should be 
selected by the president. He should ap- 
point a managing editor who possibly has 
had experience in writing or editing a paper. 
The managing editor should have full charge 
of the publication of the paper. He should 
have as his assistants, a production manager, 
a technical editor and an advertising man- 
ager. The production manager should have 
the responsibility of getting the paper printed 
and nfiailed. The staff should meet once a 
month, before publication time and plan 
for the current edition. Each member of the 
club should act as a reporter and secure news 
and material for the paper. The managing 
editor can assign a member for each type of 
news media, i.e., Civil Defense, member 
activities, news happenings in the radio am- 
ateur world, contests and projects; In plain 
language, it takes a team to make your club 
paper a success. 

Editorials by the managing editor makes 
interesting material and if the subjects are 
timely, it can put spice into the paper. The 
editor should select subjects which are of 
interest to the whole membership and avoid 
out-and-out gossip or witticisms. There are 
great many subjects which can be discussed 
about amateur radio or your club, and it is 
not necessary to list them all here. 

It is suggested that the club paper be 
protected by a notice in each edition stating 
"This publication or any part of it cannot 
be reproduced without the permission of the 
club". This protects your contributors or any 
material in the paper. Many clubs favor 




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100-500 mils. Gray aluminum cased 
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Unused cond. $10.00 
Used good $6.50 



VARACT0R SIMILAR TO MA4060A 

Good for 40 watts at 432 MC, each tested In 

circuit* W/diagram for 432 MC tnpler. 

_ M $5.00 each 

EXPERIMENTAL VARACT0R DIODES 

Package of 20 units with experimenters circuit 
explanation. Pack of 20 „,_. $1*00 

RBA-RBB-RBC POWER SUPPLY ... $25.00 

For 1 1 5 volt 60 cycle AC use, brand new In car- 
tons, powers any of the above sets. 

Cable with AC plug for above $4.00 

Cable with Ree.-Power supply plugs $7.50 

2N706 FACTORY MARKED TRANSISTORS 
„_ 7/$ 1. 00 

2N697 TRANSISTORS unmarked 1 5/$ 1. 00 

500 PIV 100 AMP Sil. DIODE $2.00 ea. 

FILAMENT TRANSFORMER $2.50 

1 15V 60C in, output 5.1 V 14.5 amp 

5.1 V 43 Amps. 
12 KV insulated, wgt 25 lbs. 

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this practice and in some cases they copyright 
their paper. All national magazines usually 
copyright their publications . Look at page 
1 of any copy of 73 Magazine and you will 
see the copyright notice. 

A favorable habit among clubs is to ex- 
change publications. Write to those clubs 
whom you feel have successful ones, offering 
to exchange yours for theirs, Reading these 
will give you an idea of their activities and 
projects, and may help your club to plan 
along the same lines. Another good idea for 
interchange between clubs is to have a 
column set aside for announcements of "what 
other clubs are doing". This creates good will 
and can be beneficial to all concerned. 

Another suggestion is to get acquainted 
with the editors of club papers in your area. 
Interchange of ideas can be beneficial to all 
concerned. A state or local editors association 
can be formed which could meet frequently 
and discuss ideas to advance the art of pub- 
lishing good club papers. There are state and 
local newspaper and magazine editors asso- 
ciations, so why not radio amateur clubpaper 
editors. 

The facts and suggestions in this article 
are not necessary to carry out to the letter 
but the fundamentals are worth following if 
you want a paper which reflects the club it 
represents. Good papers are popular* bad 
ones are thrown in the waste-basket. 

• « • JvOLi-JvA. 



OJt^Ufl I 



<^ftQ2WN 




1q w/lffWD 



Just got the chow call, OM. 



40 



73 MAGAZINE 



it 



THE HAM'S HEAVEN" 



CHABTREES ELECTRONICS 



PRESENTS 



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Phone 214—748-5361 



WRITE or CALL For Quotes or 
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High Quality Hybrid Receiver 



In these days of "commercialized" ham 
radio, there is such a variety of well de- 
signed and readily available equipment on 
the market as to make a home constructed 
station almost a thing of the past. This is es- 
pecially true of the receiver, which has al- 
ways been considered to be just a little out- 
side the ability of the average home con- 
structor. This view may not be justified, and 
this article will try to point out a few advan- 
tages to be gained by home-brewing a re- 
ceiver. Lefs briefly review the aims of this 
project: 

1. A good SSB and CW receiver, to com- 
pare favorably with commercial units in 
stability, sensitivity, freedom from cross- 
modulation and overload. 

2. Dial tuning should be smooth, with no 
backlash and no dial cords. Calibration 
should be very easily read in increments 
of one kilohertz. 

3. Few controls and very simple overall 
adjustment. 

4. Standard components to cut down cost. 

5. Construction should require only stand- 
ard home -workshop tools. Alignment 
should be accomplished with standard and 
readily available test equipment. 
Throughout the whole concept of this 

project, the cost factor and ease of con- 
struction have been vital considerations as 



well as the overall quality of the* finished 
product. To accomplish these features, both 
old and new receiver circuits were used. 
Many were obtained from 73 9 QST, the 
ARRL Handbook, etc, Some modifications 
were made to mate all the circuits together, 
but the best features of each were retained. 
The receiver is a combination tube and 
solid-state design with the basic range being 
from 3,5 to 4.0 MHz. For other bands, cry- 
stal controlled converters are used, so that 
the receiver can be constructed and other 
bands added as required. Each converter can 
be optimized for performance on one band, 
and each band is designed to cover 500 kHz. 
No doubt eyes will be looking skeptically at 
the idea of tubes in this "solid-state" age, but 
manv of us still have a lot of tubes on hand 

■r 

and it seemed pointless not to use them. 
Neither space nor power drain were prob- 
lems. Tube types were standardized to re- 
duce both initial requirements and possible 
spares. Solid-state devices were used in the 
front end and oscillator circuits in the in- 
terests of stability, and of course, could be 
carried through into other circuits if desired. 
Construction was done on two chassis of 
heavy gauge aluminum to ensure rigidity, 
good shielding between front end and audio 
if circuits, and also allow part of the 
receiver to be completed and tested as a 




Fig, I. Receiver block diagram [with plug in converter) 



42 



73 MAGAZINE 



B 


■ 











V 



A 



fe. 



Top view of the receiver. Front-end circuits up t6 
the mechanical filters are on one chassis, and if, 
audio, S-meter, BFO power supply on the other. 
Mini-boxes contain the oscillator tuned circuit, driv- 
en by the National dial, the BFO and product de- 
tector, with the BFO tuning shaft extended out to 
the front panel. A third box is shown plugged in to 
the converter socket at the rear of the chassis. This 
is a prototype 20 meter converter, but similar units 
could be plugged in for any band. 



separate unit. In fact, the audio, if AGC, 
S-meter, BFO and product detector circuits 
could be built as a project in themselves and 
added to a less expensive receiver to bring 
it up to higher standards. The audio-derived 
AGC and variable BFO are especially use- 
ful for SSB and CW operation and could be 
built into a small sub-unit and installed in 
the present station receiver. Front panel con- 
trols are kept to a minimum. Separate gain 
controls are used for if and audio, and also 
front panel control of the BFO over a fre- 
quency range of plus and minus 2 kHz of 
the 455 kHz if. For the main frequency dial, 
the National NPW dial and drive mechanism 
was chosen. It provides smooth operation 
and slow tuning rate, but should first be 
lubricated with silicon grease. This leaves 
a thin film on the gears even after extensive 
use. 

Using 000 on the dial as the low end of 
the band (3.5 for example, 010 indicates 
3,510, 020 is 3,520, etc. Admittedly some 
little effort is required to achieve this track- 
ing, but the result is well worthwhile. This 
eliminates the need for any other form of 
dial markings and gives a clear readout of 
one kHz per division. 

The three-inch deep chassis gives plenty 
of room for neat construction. Liberal use 
of tie-point strips ensures firm mounting of 
components. Instead of lacing the cabling, 
small nylon loop clamps were used. This 
makes it easy to change the wiring or install 



modifications. Every effort was made to keep 
the wiring and components "in the open" to 
facilitate servicing. 

The receiver was built from the rear end 
forward, so that the power supply could be 
used to test each circuit as it was built. The 
photo of the top of the receiver shows the 
mechanical layout. While not all that critical, 
it's recommended that not too much variation 
be allowed. The power supply uses silicon 
rectifiers in a bridge circuit, and supplies both 
regulated and unregulated B-K There are 
also voltage take-offs for the transistors and 
mechUhical filter switching diodes. 

To obtain regulated voltage for the BFO, 
a tap on Rl picks off 150 volts which is 
regulated by the Zener diode CRT The di- 
ode shown is far larger than necessary, but 
it happened to be available. An alternate 
way would be to use a miniature regulator 
tube such as an OA2 or even one of the 
octal VR150Y 

Voltage for the mechanical filter switch- 
ing diodes is obtained from the 6*3 volt fila- 
ment transformer, rectified by CR2, and fil- 
tered by CI, C2 and R2 to provide a negative 
voltage output for controlling the diodes. 

Positive voltage for the same diode circuit, 
and for the transistors, is obtained from B+ 
via R3 and R4, the latter being a 25,000-ohm 
pot (2 watts), which is adjusted to provide 
the necessary H-12 volts, This pot is a one- 
time adjustment and is mounted underneath 
the chassis. A 12- volt Zener diode is con- 
nected from the arm of the pot to ground. 
This regulates the voltage and absorbs any 
transients. 

This receiver has lots of audio, with a 
two-stage triode voltage amplifier driving 
a power output stage. Because of the con- 
siderable gain in the circuit, care must be 
taken to separate the grid and plate circuits 
and to find the best possible arrangement of 
components. The audio gain control is placed 
at the input of the amplifier. 

The AGC circuit is quite standard and is 
found in the December 1965 issue of QST. 
The circuit in the ARRL Handbook for the 
past several years will work almost as well, 
and reference should be made to these sources 
for full circuit analysis. The S-meter func- 
tions whether or not the AGC is on. Because 
past experience had proven that different 
AGC rates were seldom used, no provision 
was made for them. The AGC on/off toggle 
switch is the cnly control required on the 
front panel. The associated if stages must 










FEBRUARY 1968 



43 





l /T7 rtl 7*2^ BAND SET 
OSC. TUNING 



RESISTORS ARE 1/2 WATT EXCEPT WHERE NOTED 
CAPACITOR VALUES IN DECIMALS ARE jjF 
ALL OTHERS pF 



m 

FREQ. 
CONTROL 



Fig, 2. Front End. 



have their grids decoupled from the AGC 
line with large resistors and bypass capaci- 
tors, or even small RF chokes, Shielded 
wire may also be necessary for the AGC 
line itself. The S-meter is also adapted from 
the ARRL Handbook, and in this receiver it 
is not a calibrated function of signal level; 
it is merely used as a reference indicator. 
Considering the multitude of ideas about the 
calibration of S-meters, this is probably just 
as well. The circuit uses a single 6C4 triode 
and a milliameter of one to five miUiamps full 
scale deflection. The adjusting pots are 
mounted on a small plate under the chassis. 
To do the initial set-up, pull out the 6C4 
and adjust the meter shunt pot for maximum 
deflection on the meter. Replace the tube, 
short the AGC to ground, and adjust the 
6C4 cathode pot for zero meter reading. 
Remove the short from the AGC, and the 
meter will now follow signal variations up 
to the point where the tube's plate current 
is cut off. 

For solid-state fans, the January 1967 
issue of 73 has an excellent article on an 
equivalent circuit using a field effect tran- 
sistor. Any other circuit which may be con- 
templated must have a very high input 
impedance to not effect the AGC time con- 
stant. 

The 455 kHz if strip uses 6BA6's in two 
stages of amplification. The main feature 



here is gain; the selectivity is determined 
by the Collins mechanical filters which come 
before it. An if gain control is provided, and 
short shielded leads should be used for sta- 
bility. In-line mounting of tubes and if trans- 
formers ensures a neat wiring job. Good 
quality shielded transformers should be 
used. Referring to the photos, notice that the 
BFO and product detector tubes are mounted 
sideways and butted up against the side of 
one if transformer. To overcome the problem 
of changing the tube, the if transformer is 
held in by two screws and has long enough 
leads to enable it to be unscrewed and tipped 
over while the tubes are changed. This may 
not be the best way to do things, but tube 




Under chassis view of front-end components. The 
dual-section input tuning capacitor is coupled to an 
extension shaft, to keep it physically close to the 
input transformer. The octal socket is for the plug-in 
converters. 



44 



73 MAGAZINE 




changing will be rare and the constructional 
advantages were considerable. Incidentally, 
the 'long enough leads" should only be about 
IVi inches or so. 

The product detector uses a 7360, Both it 
and the BFO are built into a small metal 
box, with the tubes mounted on one side 
and the BFO transformer on the front. To 
make the BFO frequency variable, a small 
tuning capacitor is mounted in the box and 
the shaft extended out to the front panel. 
The box prevents any external coupling be- 
tween the BFO circuit and the if strip. It is 
firmly bolted to the chassis and all leads to 
it are brought through a grommet-lined hole 
in the chassis. If a variable BFO is not 
wanted, a crystal-controlled unit could be 
used. The circuit must have good sine wave 
output of at least 10 volts peak-to-peak. A 
transistor circuit. would work just as well, A 
vernier dial is used on the BFO control to 
give a slow and precise tuning rate, a necessi- 
ty for crowded CW conditions and of con- 
siderable help in SSB reception. 

The selectivity of the receiver is dependent 
upon the two mechanical filters which have 
been chosen as 3.1 and .8 kHz for SSB and 
CW use. The filters plug into miniature 7-pin 
tube sockets, and small copper shields are 



installed directly across the sockets to sepa- 
rate input and output circuits. All pins on the 
socket are grounded except the input and 
output Switching the filters is done by means 
of silicon diodes* 

The mixer circuit is taken from the Sep- 
tember 1963 issue of QST, and uses a 7360 
tube. All supply voltages are regulated and 
the output is fed through a special coupling 
transformer to the mechanical filters. The 
transformer used is an Admiral Corporation 
part number 88L17-1 HK2. 

A pair of Motorola field effect transistors 
are used in the oscillator. The coil and tun- 
ing capacitors are mounted very rigidly in a 
separate metal box, and all connections made 
with heavy braid. The capacitors should be 
very good quality, double-bearing units. 
Such precautions will pay off with a very 
stable, low- drift circuit, A second transistor 
stage provides good isolation between the 
oscillator and the output to the mixer. The 
balanced output transformer is home-made, 
wound on a Millen W slug tuned form. Di- 
mensions are given in the coil table. Tests 
indicate approximately 100 hertz drift during 
the entire warm up period. Good mechanical 
stability is indicated by the time-honoured 
"thump" test. 



200 P1V 
SILICON DIODE 



CR'S ARE HIGH SPEED 
SILICON SWITCHING DIODES 




53K 2W 



(T&/450V 






fig. 3. Complete schematic diagram for the hybrid receiver. 



FEBRUARY 1968 



45 




The Collins mechanical filters are shown in their 
sockets, with spring retaining clamps. The if tubes 
and transformers are Immediately to the left of the 
filters. 



Note that there is no rf stage. An octal 
socket arrangement provides for the use of 
ilug-in converters, and an rf stage can be 
3uilt on a separate module and plugged into 
this socket. This will not likely be necessary 
for good 80 meter reception, of course, the 
converters will have their own rf stages. 
To align the receiver, use good test equip- 
ment* Items required are a VTVM, an rf 
Signal generator, and a scope with 5 MHz 
bandwidth. Do the alignment in the follow- 
ing order: 

A* Power supply: Check voltages. B+ should 
be approximately 230 Vdc. Regulated volt- 
age + 150 Vdc. Adjust the positive low volt- 
age to 12 Vdc. The negative low voltage 
should be approximately 7 Vdc. Test the 
power supply without the circuits connected 



Coil 

LI 30 turns ^30 cotton covered wire, on Mil- 

len 69046 slug tuned form. 

L2 M/2 inches of $"18 wire between junction 

of LI , L4 and ground. 

L3 15 turn link wound on cold end of LI. 

L4 30 turns of $30 cotton covered wire on 

Milfen 69046 slug tuned form, 

L5 17 Turns #18 wire, 7 f$ inch long, I ■/# 

inch diameter. Barker & Williamson 25 
watt 40 meter coil with link removed, and 
5 turns removed from each end- Induc- 
tance 8 microhenries. 

T2 Primary: 60 turns #32 enamelled wire. 

Secondary; two windings of #32 enam- 
elled wire, 35 turns each, wound over the 
primary, on Millen 69046 slug tuned form. 

to it, and be sure the above voltages are 
maintained as more circuits are added* 

B. Audio section: An audio tone injected at 
the top of the volume control should be 
heard without any distortion in the speaker. 
The S-meter should deflect. Calibrate the 
S-meter as previously explained, The hum 
level should be extremelv low* 

C, IF strip: Remove AGC from the strip. 
Turn the if gain control to half position, pull 
out the first if tube, and connect 455 kHz 
from the signal generator to pin 5 of the 
first if tube socket. Connect the VTVM to 
the AGC line. Align the last if transformer 
for maximum reading on the VTVM, Replace 
the first if tube. Remove the if strip input 
from the mechanical filter. Inject 455 kHz 
through a .01 F capacitor to the grid (pin 
1 ) of the first if tube, Align the first if trans- 
former for maximum on the VTVM. As align- 
ment proceeds, keep the output level of the 
signal generator as low as possible. Recon- 
nect the AGC line to the if strip and remove 
the VTVM. 



NOTE:TI A T2 
MUST BE 
PHASED 
CORRECTLY 




(CANOED 

WITH 

AUDIO 

R GAIN] 

St 



ZNO. 1ST. IF. 2ND IF PR.DET. 
M { X E R 
7360 6BA6 6BAG 7360 



BF0 
6C4 

4 



1ST ft 2ND. AF AGC 

A.f, OUTPUT 

I2AU7 GAOS I2AU7 



$ 

METER 
6C4 



MO VAC 




>I2V 

9G3B 
O+230V 

o+tsov 



NOTE: ALL CAPACITOR VALUES GIVEN IN pF 

Fig, 4* Power supply for the High Quality Hybrid Receiver 



46 



73 MAGAZINE 



• • 





# 



'Si 






m 



Front view of the completed receiver. Note that con- 
trots are kept to a minimum. The S-meter and clock 
are on opposite sides of the dial illuminating light, 
A small metal shield normally covers this light and 
directs the fight down to the dial markings. A vernier 
dial is provided at the right for the BFO tuning ca- 
pacitor. Bottom controls are: antenna input tuning, 
mechanical filter selector switch, AGC on/off switch, 
if gain, and audio gain/power on -off. A National 
NPW dial is used for main tuning. 

D. Oscillator, mixer and BFO; Disconnect 
VFO output transformer from the source- 
follower transistor. Disconnect pin 3 of the 
second mixer tube (7360) from its input cir- 
cuit and ground the grid through a 100,000- 
ohm resistor- Connect 455 kHz signal to pin 
3 via a .01 F capacitor. Adjust the 2000- 
ohm balance pot for equal voltages on pins 
8 and 9 of the 7360, Use the VTVM for this 
measurement. There will be approximately 
35 volts on each pin. 

Connect the VTVM to the AGC line. 
Check that the filter switch circuit is work- 
ing and the filters themselves are operational. 
Adjust the 7360 output transformer for max- 
imum reading on the VTVM. Reconnect the 
VFO output transformer to the transistor- 
Using the scope, check the source terminals 








+ 




1 





Front panel removed, and the first chassis a 
mounted and ready for wiring. The mechanical filter 
sockets are at the rear, behind the dial gear box. 
The if tubes and transformers are in a row along the 
division between chassis. Audio and S-meter tubes 
are at the front. 



of both transistors for approximately 2 volts 
peak-to-peak of good sine wave output* With 
the scope at pins 8 and 9 of the 7360, adjust 
the VFO output transformer for equal ac 
voltages on the two pins. This will be about 
3 volts peak-to-peak. 

At the BFO, adjust the vernier control to 
put the capacitor at half mesh. Adjust the 
transformer in the BFO circuit to zero beat 
on the test signal. Disconnect the 455 kHz 
input signal from pin 3 of the 7360, remove 
the 100k resistor from pin 3 to ground, and 
reconnect the tuning circuit to pin 3 # Con- 
nect the signal generator to the input of the 
tuning circuit and set it to 3,6 MHz. Set the 
receiver dial to 100. Adjust the handset 
capacitor for maximum on the VTVM (still 
connected to the AGC line). The signal 
should be heard in the speaker. Check the 
tracking of the receiver over the band. There 
should be very little error over the whole 
80-meter band. Set the dial to 300, and the 
rf signal to 3,8 MHz. Adjust LI and L4 for 
maximum on the VTVM. Remove the VTVM 
and signal generator. 

This completes the alignment of the re- 
ceiver. Signals should now be heard on the 
band and the receiver should be performing 
very well. Take some time to get used to the 
feel of the control and we think you'll agree 
the time and effort were well spent. 

. . . VE1TG and VE1ADH 





o 



"How wonderful! I was afraid you might squander 
your unemployment check on groceries or rent. 



FEBRUARY 1968 



47 



Dr. Louis E. Persons, W4PJ© 

P.O. Box 1647 

R. Myers, Fla. 33902 



How to Get Better Returns 

from Your QSL 



To obtain that wanted QSL you must 
first send your QSL, quickly and accurately, 
Immediately after the QSO sit down and 
write out the QSL. In this way you can 
check and double check on the date and the 
time in GMT, The onhj time to use is Green- 
wich Mean Time, If you are not sure of 
the correct time check WWV, Hams are 
one of the largest users of WWV, but when 
one sees the many incorrect times put on 
QSL's (and logs) it seems all they do is listen 
to the tick. 

It may not seem important to be so ac- 
curate, but a rapid DX operator may work 
2 or 3 stations a minute. If your time were 
off 30 minutes on the QSL you might well 
be 3 or more log sheets off. Your card might 
be returned marked "not in log". Make 
sure, if you are changing your local time 
to GMT time, to change the date also, if 
necessary. But why not keep the clock in 
GMT; it will confuse the XYL more. Hi, 

The next most important item on the card 
is the band. Again, if you make the card 
out after the QSO you can take another 
look at the bandswitch to make sure. Many 
stations, in contests particularly, keep the 
logs by bands. 

The mode of transmission is important also 
as many awards are for Phone, or SSB, or 
CW separately. The signal report is the 
next item of information necessary to com- 
plete the confirmation of the QSO. 

It is unfortunate that there is not a stand- 
ard form used for QSL design. The easiest 
design to read quickly is the log form type 
with all of the printing on one side only. 
The log form type is made up with a sim- 
ulated line from the log sheet printed on 
the card. Everyone is familiar with the stan- 
dard ARRL log books, so it is only nec- 
essary to recopy the line in the log to the 
QSL card in making out the card accurately. 
This type QSL may be obtained from World 
Radio Lab. and others. Rut whatever form 
is used, the call letters should appear on 
the side with the QSO information, so that 



constant flipping over of the card is avoided 
in searching the logs for the contact. 

It has been said that a QSL is the final 
courtesy of a QSO. This is certainly true. 
QSLing is no burden to the amateur who 
works several stations a week, or even a 
day, but think of the station who is working 
2 or 3 stations a minute in contest style. 
He is working in this manner to give as 
many as possible the chance for a QSO and 




ultimately a QSL. QSLing for this station 
indeed is a chore. It is only right that we 
should assist this station in his QSL task in 
some manner. The usual considerate way is 
to send along with your card a Self-ad- 
dressed-stamped-envelope. The SASE saves 
most of the work for the station in not 
having to address an envelope or card, and 
also the postage involved. If postage for 
that country is not available or obtained 
from W2SAW, then the correct number of 
International Reply Coupons (as given in 
the Call Book) are sent along with the ad- 
dressed envelope. 

Also, it is not asking too much to en- 
close a small donation to help cover the 
cost of the card or the gas for the generator 
in the case of a DXpedition station. Those 



48 



73 MAGAZINE 



who go on DXpedition do so for several 
reasons. First, the enjoyment of travel and 
operating as rare DX, Second, to give the 
contacts to those who need them. The QSL 
is a necessary evil arising from the second 
reason. One on a DXpedition never expects 
to make any money on the trip or to even 
have his travel expenses paid. But some- 
how those who want the QSI/s should as- 
sume some small expense involved. The cost 
of printing a decent special or picture QSL 
to do a DXpedition justice is around $20 
per thousand and much more in other coun- 
tries. It is certainly not asking too much to 
enclose along with the SASE a small con- 
tribution to help cover this expense, any- 
where from a dime to a dollar is appropriate. 
While some hams revolt at the thought of 
"paying for a QSL" these individuals think 
nothing of paying to enjoy their other hob- 
bies such as the green fee to play golf, the 
bait boat, gas, etc, for fishing, the film 
for their camera for photography and the 
cost of stamps for their stamp collection, 
QSLing is just one of the small expenses 
in enjoying the greatest hobby of them all, 
Amateur Radio. 

When working a station ask him where 



to QSL or if he is working contest style, 
listen and he will announce every few min- 
utes QSL information. If he announces the 
call letters only of the QSL manager or 
perhaps his home call be sure you have it 
correct. Then be sure that you look up the 
QTH in a recent Callbook. Recent is one 
dated the current year. If you do not have 
one which is recent, borrow one from some- 
one else or look for the correct QTH in 
one of the magazines. The envelope with 
the QSL, SASE, and the contribution should 
be mailed by Air Mail if going out of the 
country. There are many other secrets used 
to obtain QSL's such as writing a letter to 
the station, along with your card in his na- 
tive language, enclosing pictures, commem- 
orative stamps, and even to sending him a 
QSL already made out to you just waiting 
for his signature. Blank cards can be ob- 
tained for this purpose. 

While the above mentioned procedures 
may seem elementary to many readers, all 
QSL managers will agree that most of them 
are violated daily on cards received. Take 
pride in your QSL and QSLing procedure 
and vour results wall be pleasing, 

. . . W4FJG 




HEY! HOW ABOUT THAT 



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• MODEL SWB-2 

•READS FORWARD AND 
REFLECTED POWER 
SIMULTANEOUSLY 

• "EASY READ 4 ' METERS 

• USE FOR REFERENCE 

POWER METER 

• DUAL 1QO-MICROAMP 

METER MOVEMENTS 

• LOW INSERTION LOSS 

• SIZE-5"X2"X2" 



$15.95 




umm 



THE BEST 
VALUE WE 

HAVE 

EVER 
OFFERED! 



MAY BE LEFT 

IN LINE, UP 

TO 2000 WATTS. 



GOOD THROUGH 
2 METERS 



SINCE 1933 



FAST SERVICE 



Phone CY 4-0464 



I 
I 
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QUEMENT ELECTRONICS 

1000 SOUTH BASCOM AVENUE SAN JOSE, CALIF °*NIA 

"Northern California's Most Complete Ham Store" 95128 



I 
I 
I 
I 
I 
I 
I 
I 
I 
I 
I 




FEBRUARY 1968 



49 



— 



Katashi Nose KH6IJ 
Physics Department 
University of Hawaii, 
Honolulu, Hawaii 96822 



Tips for the CW Contester and DX'er 





Equipment 

Go as high power (to the legal limit) 
as your budget and facilities will allow, 
"Low power is all one needs for DX" is 
sour grapes and unrealistic. I have worked 
the East coast of the USA from Hawaii on 
160 meter CW with 25 watts to a guy 
wire and have been on the receiving end 
of a chap in Arizona using 6 milliwatts on 
28 MHz CW, but that's for the birds if 
you want to enjoy DX without waiting for 
that freak break. 

Low power may be fine for the higher 
frequency bands but on the lower frequency 
bands it is a waste of time, Likewis 
stacked arrays, long booms, and high struc- 
tures are fine if you can afford them, but 
I have found that the mental strain in a 
wind storm is not worth the price. Frankly, 
there is little to choose between a quad 
and a Yagi as long as you have some kind 
of a Beam with reasonable radiation effi- 
ciency, I have been through many cycles 
including stacked four over four beams, 
rhombics, and 45 foot booms, some of which 
are described in the antenna handbook and 
magazine articles. 

A good receiving location is more impor- 
tant than long booms and superheights or 
yagi versus quad arguments. Let's face it, 
some of us are not situated to work DX. 

Would you care to compete in the In- 
dianapolis Classic in your family car? Get 
the best there is that you can afford, either 
homebuilt or commercial made. The quali- 
ties to look for in a CW receiver are con- 
trollable selectivity, fast recovery and free- 
dom from front-end overloading. My con- 
test contacts jumped a good %d% when T 
switched from conventional if to mechanical 
filters, 

Lest you think that I am a button pusher, 
let me say that I entered the first few DX 
contests with a microphonic 201-201-112 
combination in which one did the fine tun- 
ing by body English (leaning forward and 



backward to the right position after each 
transmission). Later a National FB7 was 
used which had only M inch (not misprint) 
of bandspread for the whole 20 meter band. 
There was no such thing as zero beating a 
station because one couldn*t find zero beat. 
However, for those who were fastidious, 
one could shut off the plate voltage and by 
holding the key down and letting the fila- 
ment voltage provide a 60 cycle buzz of a 
sort, one could get near the correct fre- 
quency (wavelength in those days,)* 



To zero or not to zero 

In CW work there is no choice but to 
zero beat. Listening up five (or ten) mere- 
ly serves to clutter up the band. How would 
you like to work in a net in which each 
station was on a different frequency? A 
party line is what you want, so that every- 
one knows what is happening and where he 
stands. 

The average CW man is smart enough to 
learn very quickly which way the wind is 
blowing. It doesn't take him long to find 
out that he is making an ass of himself 
by getting out of phase, 

A good operator can take complete con- 
trol of a frequency, I have heard operators 
who spend more time complaining of the 
QRM on their frequency, and trying to 
line them up in proper numerical order, 
than working them. If the QRM gets out 
of hand, one can always get out from under 
and sneak up on a new frequency. 

Work stations and reduce the pile in 
natural order, the loudest ones first (with 
exceptions mentioned later) and get rid of 
them so you can work down into the weak 
layer. If vou find that they are all about 
the same strength, tune off to one side 
just a litde (something you cannot do with 
SSB very far). It is very seldom that every- 
body will be exactly on the same frequency, 
Work slightly around the edges of your 



SO 



73 MAGAZINE 



frequency and back and forth across your 
frequency. Let your ear separate the slight- 
est frequency differences. If you cannot do 
this you need more practice. 



The operator 

One must keep in condition to be able 
to work a successful contest. Be able to copy 
50 words per minute in your head and to 
take down 35 words per minute solid. Log- 
keepers and spotters are a waste o 4 time 
and as necessary as the fiftli wheel. 

The bottleneck is not spotting or log- 
keeping, but the operator on the other 
end. You can catch up on your log keeping 
while the other operator is sending. You 
will find ample time for logkeeping and 
other bookkeeping chores while the other 
fellow is sending, except when you hit an 
operator who has been around contesting a 
lot. If you meet two or three of these fel- 
lows one after another you will find your- 
self three or four contacts behind in 
logging. However, there is a trick in this 
situation too. Simplify your numbering sys- 
tem, what difference does it make to any- 
body whether you pass out a 599 or 579, 
you might as well give them all 599. The 
chances are he will also give you a 599 so 
why complicate bookkeeping. Moreover, a 
good report makes the other operator think 
that he is getting in loud and clear and 
will make the contact short and fast. 

To squeeze out that weak one employ 
the following technique. Hold your breath, 
close your eyes, cock your head and con- 
centrate. Incidently, I have found that this 
works for hearing tests as well. I presume 
you use earphones, because if you use loud- 
speakers you are not a CW Dx'er, note I 
didn't say phone Dxer because quite a 
number of hams apparently don't know that 
one can monitor the quality of ones trans- 
mission by using earphones and your own 
receiver. If you use a transceiver, of course 
you are out of luck. 

The stethoscope type of earphone allows 
you to wear glasses in comfort since you 
will be operating for 8 hour stretches. The 
old earmuff type (Brandes, Baldwin) phones 
made your ears feel as if they were ready 
to drop off after a few hours of use. 

When your contacts start falling off to 
less than 30 an hour, it is time to catch up 
with a catnap. Get a good rest of at least 
six hours every night. 

FEBRUARY 1968 



Special techniques 

Unless you can get into the dense ham 
population area you might as well forget 
about becoming one of the top scores. In 
the ARRL DX Contest, this means that you 
must put in a good signal into the second 
and third call areas for at least 14 hours a 
day. There seem to be a lot of W6s but 
you will find that they get fished out very 
quickly. The second and third districts will 
furnish an inexhaustible supply of weak 



ones. 



If it is a world-wide competition (CQ 
type), unless you are situated to work into 
Europe, you are not going to be among the 
world high. The South American CW con- 
tester is a rare bird, and you can't get 
many CW multipliers from the North Amer- 
ican continent. 

Know when special openings are going 
to take place and be there with proper 
schedules. Special openings sometimes are 
of only a few minutes duration. For in- 
stance you can work that Wl on 160 meters 
just as the sun in rising on the East Coast. 
He will peak up and rise out of the noise 
level and disappear again only once. 

On the low frequency bands, don't get 
sucked in by the first loud station who calls 
you. He can serve a useful purpose by using 
him as a bait. Let him call you but don't 
answer for a while. His cry of anguish will 
alert the band to the fact that something 
interesting is underneath. When the pack 
becomes thick, pick them off one by one. 
This technique will save a lot of CQing on 
your part on the low frequency bands. 

However, certain non-DX types will fool 
you because he gives up easily and quits 
after a few calls. Cultivate a clientele and 
learn their habits and foibles. You will find 
that certain ones will always be there as 
soon as you open up on the band. Make a 
habit of opening up on a certain band at 
a set time, the old timer contester will be 
there waiting for you. W9IOP, W4KFC, 
W3MSK, W3GRF, W6RW, to name a few, 
don't get rattled easily. They will quit if 
they don't get you in the first few calls, 
knowing full well that their time will come 
around when the hue and cry subsides. 
Learn to recognize fragments of familiar 
calls. 

Don't fold up in the face of competition, 
the opposition can always blow up a power 
transformer or have a social engagement 



51 



- 






the second weekend. Don't show your hand 
but keep the opposition guessing, and in 
this respect serial number sequences are 
less desirable since it involves one more 
type of bookkeeping. Multipliers will take 
care of themselves if you pile up the volume- 
Do not keep the other station guessing 
by changing pace. Set up a definite sequence 
and stick to it. Deviation from a sequence 
or change of pace only serves to confuse 
the operator at the other end. When you 
go back to a station, his call will be lost 
in a pile of QRM and he will know who 
you went back to. Therefore it is important 
that you reassure him by signing his call 
at the end of an exchange plus your call. 
Signing your call at the end advertizes your 
presence on the band and prevents queries 
as "what is your call?" Sign your call only 
once, no more, after all, they know who 
is being hunted. A mere "break" only 
serves to get several other stations acknow- 
ledging you, each one thinking that he has 
nailed you. 

Learn to copy a fast sender through a 
slow sender. Many times you will find that 
someone who calls very slowly will be in har- 
ness with a fast caller. Get rid of the fast 
caller with a fast exchange and then go 
back to the slow one, He won't know the 
difference. If the slow caller (long caller) 
unexpectedly signs early, a short "QRZ" 
will keep him going for another round until 
you are ready for him. 

Sometimes you will find two stations send- 
ing you a serial number each thinking that 
he has mailed you, A short "ok" at appro- 
priate intervals will hold both for you until 
you sign out both calls. However, this last 
trick calls for considerable practice and 
finesse because you can get into an awful 
mess by losing synchronism. 

Logkeeping 

Use carbon paper and send in the carbon 
copy (FCC says you must keep original 
logs.) The standard ARRL logbook is good 
for only 29 contacts per page and is not 



VHF-UHF 



Converters and Preamps 
for 50 thru 432 Mc. 

Write tor literature. 

Parks EUctronics, 418 S.W. First BtavtrtM, Ors, 



recommended for contests in the order of 
4000 contacts. 

It is amazing how well one can keep 
track of duplications after a few years of 
practice. The average contester has a pretty 
foolproof filing system so let him do the 
work for you. You will not have time to 
keep track of multipliers at first, Leave 
that chore to a slack period, You are less 
liable to make mistakes this way. 

Hang on to that ballpoint pen at all 
times and don't lay it down. Learn to send 
on the bug while holding the pen in the 
same hand. The other hand can be arrang- 
ing papers or adjusting controls while you 
are sending. Can you imagine picking up a 
pen and laying it down 8000 times which 
is what one would do in the course of a 
good hot contest. 

A parting shot 

Over 8000 contacts were made in the 
1967 ARRL DX Contest from a 5000 square 
foot city lot using a tribander and antenna 
system described in a recent magazine art- 
icle with a 40 foot tower from 160 meters 
through 10, Tower guy wires were used as 
radiators for the low frequency bands. For 
the contest antagonist, let me say that I 
have been through the public interest and 
necessity bit. Ask any old timer about the 
relav circuit from KA1HR (Manila, OM1TR 
(Agana) to NY2AB (Coco Solo) to W3CXL 
(Washington DC). There was none of this 
**a phone match is in progress and a clear 
channel will be appreciated" stuff. Message 
traffic ran up as high as 4000. Traffic han- 
dling, ragchewing, net operation, RTTY, 
VHF, have been tried but there is nothing 
like a good hot DX contest to test men and 
equipment. 



DXERS and DXERS-TO-BE 

Want to keep up to the minute of what't 
happening DXwise? Subscribe to Gut 
Browning W4BPD** new weekly DXERS 
MAGAZINE, 16 pages of DX events, com- 
ing up DXpeditions, QSL info, pix, etc. 
Rates, US surface $8.50. US air mail $10, 
West Indies $16.50, S. America and Eur- 
ope $19, rest of world $28. 

The DXERS MAGAZINE 
c/e W4 BPD 

Route I, Boi I6I-A, 
Cordova, S.C., U.S.A. 



52 



73 MAGAZINE 



STILL 




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Ross Sheldon K4HKD 
3313 Avery St. 
Huntsville, Alabama, 35805 



How to Publicize Your Club 



I've never met an editor, nor even seen 
one— except in **B" movies. But, as a re- 
tired army public relations officer and a 
part-time freelance writer-photographer, I 
have had no difficulty getting publicity 
stories into print, without coming any closer 
to the editor than my mailbox and his. They 
don't ALL get printed, but MOST of them 
do. 

The only problems I have had with get- 
ting stories about the Huntsville Amateur 
Radio Club into the newspaper and onto 
the radio are two: Getting the club mem- 
bers to do something worth writing about— 
and getting up the energy to write it up 
and drop it off at the local papers and 
radio stations when there is a good pro- 
gram on TV or the DX is rolling in. 

And that last is the principal obstacle 
to most club publicity chairmen in getting 
up a good story— getting up the energy to 
get it out, 

But ? lest someone say; *Tt*s easy for a 
pro to talk", let me show you how easy 
it really is to get publicity— yet how diffi- 
cult it really can be, if you don't under- 
stand a few simple facts of life about pub- 
lic relations. 

Fact Number One: The editor wcmts to 
print your story. 

An editor's favorite dream is of mail- 
bags full of "good copy" sitting on his desk 
each morning; all well-written and accom- 
panied by a stack of usable pictures. Ac- 
cording to this dream-fantasy, all he has to 
do is shuffle through the pile, pick out 
those he likes the best and hand them to 
the copyboy to take to makeup. 

Fact Number Two: There are a lot of 
people in this world trying to make his 
dream come true— for free. 

Each day the metropolitan newspapers 
receive mailbags full of handouts from 
every imaginable source, mailed by public 
relations men trying to get their clients 
business into print. 



Cypress Gardens deluges editors with pic- 
tures of sweet young things on water skis. 
Miss Fickle Week peeks out of another 
envelope sent by the public relations firm 
representing the pickle account. A picture 
of the town mayor signing a proclamation 
for "National Boy Scout Week" in com- 
pany with the local scoutmaster and a toothy 
scout is next. And, as for the government: 
"Private Schnertz, son of Mr, and Mrs. J. J, 
Schnertz— "I The departments of Agricul- 
ture (national, state and county agent) give 
the editor twice as much farm news in a 
day as he has room to print in a week. 
Every government agency, official, office- 
holder (or candidate for same) has an 
"image" to project. 

And anybody who is anybody who comes 
to town, or just passes through it, has an 
advance copy of the event on every editors 
desk three days ahead, complete with pic- 
tures. 

The moral to both Fact Number One and 
Fact Number Two is Fact Number Three: 

The editor wants your story, but it had 
better be good; because, friend, it's got a 
lot of competition. 

Now to give the editor what he thinks 
is good, what does it take—a degree in 
Journalism or English Composition? 

Well, it would help if you could write. 
But writing the simple routine news story 
of club activities is simple. Every ladies 
club has someone doing it. Take any club 
meeting story from the daily paper; scratch 
out the names, dates and places; substitute 
those for your own club; retype and send 
it in and you have as good a routine club 
news story as anyone else* 

Maybe even better, if you get the facts 
straighter, the names spelled right, type it 
double-spaced with wide margins and have 
your name and phone number at the bottom 
in case the editor has a question he wants 
to check out. 

Get these routine stories in from one to 



54 



73 MAGAZINE 



two days ahead of the meeting. It takes 
time to select, edit and print them— and 
there is no filing cabinet by the editors 
desk to "hold until release date". (The edi- 
tor knows he will have a new slush pile 
tomorrow anyway.) 

But these routine stories are the least 
important part of your job as public rela- 
tions man for your club. Your main job is 
the clubs relations with the public; And the 
last thing the public wants to know about 
is that you held a meeting, or what went 
on in it. They don't belong to your club 
and could care less. What the public wants 
to know is— what is your club doing of 
interest to them? 

Is your club doing anything which affects 
the public or is in the public interest? Is 
it doing anything the public would find 
interesting, informative, entertaining or from 
which the reading public could benefit in 
some way? Can any eye-catching picture 
be used? (Remember Miss Pickle Week 
and the young lady on water skis? What 
was really "newsworthy" about them? Noth- 
ing at all. Many "beauty queens" are non- 
winners of contests which never happened, 
merely paid models to advertise a product 
or an event the public is expected to pay 
for.) 

Getting such "angles" to "make a story" 
is the public relations man*s principal pre- 
occupation. 

And the principal problem associated with 
this is getting the club to go along with 
the story. Many club members do not realize 
that to be in the news they must be news- 
worthy; they must do something worth 
writing about. 

To give you and your club ideas for op- 
portunities to present your club and ham- 
dom favorably in the press, following are 
some headlines from the local papers about 
the HARC— with a summary of the story 
that accompanied them. All stories included 
the time and place of the clubs meeting 
and used pictures wherever possible. 



"Hams Donate Library Book 11 

Picture of a club representative and the 
city reference librarian examining the latest 
issue of the Callbook which the club donated 
to the library. The story explains that any 
ham may phone the reference desk and the 
librarian will give him the address he needs. 
The meaning of ham calls and how they 



differed from CB calls was included in the 
story. 

"Hams To Help On UNICEF Drive" 

The HARC "Spook Patrol" (see 73, Nov 
67) is a regular Halloween event. The story 
tied in with the national UNICEF drive held 
at the same time. 

"Hams To Promote Mobile Frequency' 1 

A picture of a Sixer under the dash 
headed a story on how hams used a special 
high frequency for local emergency nets. 
Radio wave characteristics, low cost of VHF 
equipment, hams tie-in with Civil Defense 
and number of hams in Huntsville ("more 
than rest of the state combined*') were in- 
cluded in the story. 

"Radio Club Members Practice 
Tracking Clandestine Transmitter 11 

A page-wide spread of pictures showed 
hiding a transmitter and followed a ham 
with mobile and hand-held "sniffer" as he 
went directly to it. The civil defense, nat- 
ional security and rescue aspect of the hams 
tracking ability was stressed. 

"City Ham is State Champ" 

A picture of the club member who placed 
highest in the sweepstakes receiving an 
award from the SCM. 



"Ham Radios Early Days Talk Planned" 

Talk by an oldtimer* Angle: Todays hams 
bounce signals off the moon, put up their 
satellites and talk as casually to a ham in 
Singapore as to one a 100 miles away. Pro- 
gress made by the hams in developing com- 
munications over the years was stressed, 

"Radio Club Demonstrates At The Mall" 

Picture of demonstration stations operat- 
ing inside the city's largest enclosed shopping 
center. Citizens were invited to send messages 
by amateur radio from the display area. 
The National Traffic System and emergency 
nets were featured both in the story and 
on posters around the demonstration, Moral: 
Public relations men use more than a news- 
paper to get the image of their client 
across to the public, 







FEBRUARY 1968 



55 



"Charity Drive Calls For Hams 11 
"Radio Club To Aid Project" 

Another double. Both stories on the same 
subject. The March of Dimes asked our 
help— and the hams said ok. Two stories out 
of one a few days apart. Moral: When you 
milk your cow, strip her clean, 

"Radio Club Plans Auction 11 
"Wonder If It Still Works?" 

The last headline was under a picture of 
three hams examining a piece of surplus 
gear to be auctioned off. A pile of interest- 
ing gear in foreground and background 
made the picture newsworthy and got 10 
column-inches in the small morning paper 
and 24 column -inches in the afternoon, 
The auction that Friday night was crowded! 
(Finagle note: None of the pictured stuff 
was actually for auction. The three hams 
worked in a local electronics store which 
stocked the stuff and the picture was taken 
in the corner of their warehouse! ) 

"Ham Club Forms Speakers Bureau" 
"Ham To Speak To Sertoma" 
"Camera Club To Hear Ham" 

The first story listed some of the subjects 
various members were qualified to speak 
about (from flower raising to lasers). Later 
stories featured the ham's picture and sub- 
ject, and, incidently.something about the 
club he was talking to. In the public rela- 
tions trade this is known as "piggy-back", 
"coat-tail" or "free-ride" publicity. That is, 
you get in your licks by riding the other 
fellows wagon. 

"Ham Aids Ship At Sea" 

"Local Operator Helps Man On Ship In 

Atlantic" 

A local ham was asked by one in New 
England on twenty if he could get a station 
in Mobile, Alabama to meet a maritime- 
mobile later that day. A seaman had heard 
his brother was in a Mobile hospital as a 
result of an auto accident A directional 
call on 75 on the state frequency got a sta- 
tion up on twenty from, of all places and 
Glory-to-be-for- Alabama-publicity— the bat- 
tleship "Alabama" in Mobile Bay! (Abso- 
lutely no Alabama newspaper editor would 
have refrained from printing that story- 
complete with a picture from the morgue 
of "the great battleship"!) Moral: Some- 
times you just cant lose. 



"Each Night Hams Sit Down To Talk" 

With half a page of text and pictures of 
homebrewed fixed and mobile rigs, the 
feature story told of the nightly Alabama 
Single Sideband Net, the National Traffic 
System, emergency operations and mobile 
units. The low cost of home-brewed gear and 
the local club activities were stressed, 

"Ham Operators Monitor Storm " 

(See 73, June '67, p 117 "Ham Public Serv- 
ice and Broadcast Stations",) Frequencies 
of local and regional hurricane nets were 
given for the benefit of shortwave listeners. 
Local newspapers and radio and TV stations 
borrowed receivers and listened to the ham 
hurricane nets, giving them credit for their 
activities. Five local stations broadcasted 
daily tape-recorded reports by a local ham 
on what the ham hurricane nets were doing. 



"Junior Ham Action" 

Hearing of a CB Jamboree in town, I 
suggested we display our mobile emergency 
bus in the parking lot for the benefit of 
interested CB'ers. We then photographed 
three of our junior-high hams in the bus 
with a story whose lead said the kids 
"stole the show" at the jamboree! (Which 
they did, but the paper caught H— from the 
CB'ers for saying so!) 

11 Pool Efforts To Curb Accidents" 

"Jeep Patrol, Radio Hams Join Memorial 

Day Watch" 

(See "El Paso Roadblock", CQ June, 
1961). Though from another part of the 
country, this is included to show a type of 
skullduggery a public relations man some- 
times has to pull to get his client in 
print. 

The local jeep-mounted sheriffs reserve 
were previously featured in the paper, with 
a statement that they were handicapped for 
lack of radios. I suggested to them that, with 
a long weekend holiday coming up, the 
sheriffs reserve and hams could team up 
with a highway safety patrol demonstra- 
tion stakeout to prevent accidents and as 
a training exercise* 

Both groups agreed, but an immediate 
impasse was reached. 

Neither wanted to take the initiative to 
organize the operation. Each said: "If they 



56 



73 MAGAZINE 



want to put it on, we will help them"\ 

So— I phoned the head of each group as 
a presumed agent of the other which was 
"putting on the operation" and asking them 
to help! 

To "avoid a clash of plans" (each thought 
the other was doing the planning) I pro- 
posed that as hams were only "communica- 
tions men" and the sheriffs reserve were 
the"police experts", that each stick to their 
specialty and the hams provide the com- 
munications for the sheriffs reserve which 
would conduct all other aspects of the oper- 
ation. Pictures of ham mobiles and sheriffs 
jeeps side-by-side were in all papers for 
days in advance and when they were seen at 
highway intersections over the holidays the 
public held its speed down. (Result, there 
were no accidents or speeding tickets is- 
sued throughout the long weekend.) 

Moral: Watch the daily papers for activ- 
ities and problems of other groups and take 
advantage of a chance to do a little mutual 
backscratehing— even if you have to sidle 
up to the other fellow to do it. 

Many other stories, with pictures, were the 
usual routine: Field Day, code classes, ham- 
fest, installation of officers, program topics, 
etc. All are ideas you can use in your 
club* 

. i . K4HKD 

Line Noise in the 
Heath Monitor Scope 

For you who have a Heath monitor scope, 
a note on intermittent line noise. If you ex- 
perience this, try turning off the scope while 
receiving a weak signal. A possible cause of 
this noise is due to the internal construction 
of the CRT. Checking the schematic, you 
will find that your transceiver output looped 
through the scope "hopefully" gives you the 
trapezoid pattern on transmit. On the receive 
mode, the scope uses its internal vertical 
amplifier. However, the capacitive voltage 
divider, found on the back panel (Xmtr Attn 
Swatch) is in the circuit at all times. After 
several years of operation, the CRT on my 
scope became an intermittent cause of much 
dandruff scratching. After two days on the 
bench, I found that pin 10, a vertical plate, 
was arcing to pin 4 deep in the neck of the 
CRT tube. Cut back the sensitivity on the 
transmitter attenuation switch, and save 
$27.05 for a new tube, 

. , , Ray Kashubosky K8RAY 

FEBRUARY 1968 



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These valuable EXTRA features 
included in both editions! 

• QSL Managers Around the 
World! 

• Census of Radio Amateurs 
throughout the world! 

• Radio Amateurs* License 
Class? 

• World Prefix Map! 

• International Radio 
Amateur Prefixes 



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Radio Amateurs* Prefixes 
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A.R.R.L. Phonetic Alphabet! 

Where To Buy! 

Great Circle Bearings! 

International Postal 
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67 






Technical Aid Group 






If you have a question which can be 
answered adequately through the mail, 
look through the following list of TAG 
members and write to one whose specialty 
covers your problem area. Be sure to ex- 
plain your problem clearly and write leg- 
ibly. Enclose a Self Addressed Stamped 
Envelope for a reply, Do not ask a mem- 
ber to design a piece of equipment for you. 
The purpose of this group is to assist the 
ham with problems he encounters in the 
course of building or trouble shooting. 

John Allen, K1FWF, high school student, 
51 Pine Plain Road, Wellesley, Mass. 02181. 
HF and VHF antennas, VHF transmitters 
and converters, AM, SSB, product data, and 
surplus, 

Bert Littlehale, WA1FXS, 47 Cranston 
Drive, Groton, Conn. 06340, Novice trans- 
mitters and receivers, AM SSB, HF re- 
ceivers, test equipment and homebrew pro- 
jects gone wrong. 

Bob Groh WA2CKY, BSEE, 123 Anthony 
Street, Rochester, New York 14619. Special- 
izes in VHF/UHF solid-state power ampli- 
fiers, but will be glad to make comments 
on any subject, 

Jim Ashe W2DXH, R.D. 1, Freeville, New 
York, Test equipment, general, 

G, H, Krauss, WA2GFP, BSEE, MSEE, 
70-15 175 Street, Flushing, New York 11365, 
Will answer any questions, dc to microwave, 
state-of-the-art in all areas of communica- 
tions circuit design, analysis and use. Offers 
help in TV, AM, SSB, novice transmitter 
and receivers, VHF antennas and convert- 
ers, receivers, semiconductors, test equip- 
ment, digital techniques and product data. 

Don Nelson WB2EGZ, EE, 9 Greenridge 
Road, Ashland, New Jersey 08034, VHF an- 
tennas and converters, semiconductors, selec- 
tion and application of vacuum tubes, 

Stix Borok WB2FFY, high school student, 
209-25 18 Avenue, Bay side, New York 
11360. Novice help. 

Clyde Washburn K2SZC, 1170 Genesee 
Street, Building 3, Rochester, New York 
14611, TV, AM, SSB, receivers, VHF con- 
verters semiconductors, test, general, prod- 
uct data. 



Richard Tashner WB2TCC, high school 
student, 163-34 21 Road, Whitestone, New 
York 11357. General 

J. J. Marold WB2TZK, OI Division, USS 
Mansfield DD278, FPO San Francisco, Cali- 
fornia 96601. General- 
Ira Kavaler, WA2Z1R, RSEE, 671 East 
78 Street, Brooklyn, New York 11236. SSB 
transmitting, color TV, computer program- 
ming and systems, digital, radio and remote 
control, rf transmission lines, dipole design, 
audio amplifiers, linear and class C rf ampli- 
fiers. 

Fred Moore, W3WZU, broadcast engineer, 
4357 Buckfield Terrace, Trevose, Pa. 19047. 
Novice transmitters and receivers, HF and 
VHF antennas, VHF converters, receivers, 
AM, SSB, semiconductors, mobile, test equip- 
ment, general, product data, pulse tech* 
niques, radio astronomy, bio-medical elec- 
tronics, 

Theodore Cohen W9VZL/3, BS, MS, PhD, 
261 Congressional Lane, Apartment 407, 
Rockville, Maryland 20852. Amateur TV, 
both conventional and slow-scan. 

Walter Simciak, W4HXP, BSEE, 1307 Bal- 
timore Drive, Orlando, Florida 32810. AM, 
SSB, Novice transmitters and receivers, VHF 
converters, receivers, semiconductors, mobile, 
test-equipment, general, 

James Venable K4YZE MS, LLB, LLM, 
119 Yancey Drive, Marietta, Georgia. AM, 
SSB, novice gear, VHF, semiconductor and 
test equipment 

J. Bradley K6HPR/4, BSEE, 3011 Fair- 
mont Street, Falls Church, Virginia 22042 
General, 

Wayne Malone W8JRC/4 BSEE, 3120 
Alice Street, West Melbourne, Florida 32901, 
General 

Bruce Creighton WA5JVL, 8704 Belfast 
Street, New Orleans, Louisiana 70118* Nov- 
ice help and general questions. 

Douglas Jensen, W5QGJ/K4DAD, BA/ 
BS, 706 Hwy 3 South, League City, Texas 
77573, Digital techniques, digital and linear 
IC's and their applications. 

Louis Frenzel W5TOM, BAS, 4822 Wood- 
mont, Houston, Texas 77045. Electronic 



58 



73 MAGAZINE 



keyers, digital electronics, IC's, commercial 
equipment and modifications, novice prob- 
lems, filters and selectivity, audio. 

George Daughters WB6AIG, RS, MS, 1613 
Notre Dame Drive, Mountain View, Cali- 
fornia. Semiconductors, VHF converters, test 
equipment, general. 

Glen H. Chapin, W6GBL, 3701 Trieste 
Drive, Carlsbad, Calif. 92008. HF and VHF 
antennas; novice transmitters and receivers, 
VHF converters, semiconductors, receivers 
AM, SSB, general, surplus, 

Tom O'Hara W6QRG, 10253 East Nadine 
Temple City, California 91780. ATV, VHF 
converters, semiconductors, general ques- 
tions. 

Steve Diamond WB6UOV, college student, 
Post Office Box 1684, Oakland, California 
94604. Repeaters and problems regarding 
legality of control methods. Also TV, novice 
transmitters and receivers, VHF antennas 
and converters, receivers, semiconductors, 
and product data. 

Orris Grefsheim WA6UYD, 1427 West 
Park, Lodi, California 95240, TV, HF an- 
tennas, SSB, VHF antennas and converters, 
receivers, semiconductors, and general ques- 
tions, 

Hugh Wells, W6WTU, BA, MA 1411 18th 
Street; Manhattan Beach, Calif. 90266. AM, 
FM receivers, mobile test equipment, sur- 
plus, amateur repeaters, general, 

Howard Krawetz WA6WUI, BS, 654 
Barnsley Way, Sunnyvale, California 94087 . 
HF antennas, AM, general. 

Carl Miller WA6ZHT, 621 St, Francis 
Drive, Petaluma, Calif. 94952. Double side- 
band. 

Howard Pyle W70E, 3434-74th Avenue, 
S.E., Mercer Island, Washington 98040, 
Novice help. 

Ronald King KSOEY, Box 227, APO 
New York, New York 09240. AM, SSB, 
novice transmitters and receivers, HF re- 
ceivers, RTTY, TV, test equipment, general. 

Charlie Marnin W8WEM, 3112 Latimer 
Road, RFD 1, Rock Creek, Ohio 44084. 
Genera] technical questions. 

Michael Wintzer DJ4GA/W8, MSEE, 718 
Plum Street, Miamisburg, Ohio 45342. HF 
antennas, AM, SSB, novice gear, semicon- 
ductors, 



Roger Taylor K9ALD, BSEE, 2811 West 
Williams, Champaign, Illinois 61820. An- 
tennas, transistors, general. 

Michael Burns Jr. K9KOI, 700 East Vir- 
ginia Avenue, Peoria, Illinois 61603. AM, 
SSB, receivers, transmitters, digital tech- 
niques, novice help, general 

Jim Jindrick WA9QYC, 801 Florence 
Avenue* Racine, Wisconsin 53402. Novice 
transmitters and receivers, general. 

John Perhay WA0DGW/WA0RVE, RR 
#4, Owatonna, Minnesota 55060. AM, SSB, 
novice transmitters and receivers, HF re- 
ceivers, VHF converters, semiconductors, 
mobile, product data, general. Has access 
to full specifications on almost all standard 
components presently catalogued by Amer- 
ican manufacturers. 

David D. Felt WA0EYE, television engi- 
neer, 4406 Center Street, Omaha, Nebraska 
68105, Integrated circuits, transistors, SCR's, 
audio and rf amplifiers, test equipment, 
television, AM, SSB, digital techniques, 
product data, surplus, general 

Tom Goez K0GFM, Hq Co USAMAC, 
Avionics Division, APO New York, New York 
09028, HF antennas, mobile, airborne com- 
munications equipment, particularly Collins 
and Bendix gear, AM, FM, or SSB-HF, 
VHF, UHF, general 

Robert Scott, 3147 East Road, Grand 
Junction, Colorado 81501. Basic electronics, 
measurements; 

PFC Grady Sexton Jr. RA 1146 1755, 
WA1GTT/DL4, Helmstedt Spt. Detachment, 
APO New York 09742. Help with current 
military gear, information from government 
Technical Manuals, 

PFC William A. Youdelman DL4FK/ 
WA6LRS, DSMA B-4, c/o HHB, 6 Rn, 61 
Aty, APO New York, New York 09225. 
Invites questions from memhers of US Forces 
in Europe regarding licensing or any tech- 
nical questions they care to ask. 

Eduardo Noguera M. HK1NL, EE, RE, 
Post Office Box Aereu 774, Barranquilla, 
Columbia, South America. Antennas, trans- 
mission lines, ast experience in tropical 
radio communications and maintenance, HF 
antennas, AM, transmitters and receivers, 
VHF antennas, test equipment and general 
amateur problems. Can answer questions in 
Spanish or English, 






FEBRUARY 1968 



59 



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Help with all types of RTTY both com- 
mercial and military. Also data techniques. 
Covers conversion of military RTTY equip- 
ment. 

Frank M. Dick WA9JWL, 409 Chester 
St., Anderson, Indiana 46012. Will answer 
queries on RTTY, HF antennas, VHF anten- 
nas, VHF converters, semiconductors, mo- 
bile, general, and microwave. 

Gary De Palma WA2GCV/9, P.O. Box 
1205, Evanston, 111., 60204. Help with AM, 
Novice transmitters and receivers, VHF 
converters, semiconductors, test equipment, 
digital techniques and all general ham 
questions. 

Charles Marvin W8WEM, 3112 Lastmer 
Road, RFD #1, Rock Creek, Ohio 44084. 
Will help with any general amateur prob- 
lems. 



D. E. Hausman VE3BUE, 54 Walter 
Street, Kitchener, Ontario, Canada. Would 
like primarily to help Canadians get their 
licenses. Would be able to help with Novice 
transmitters and receivers. 

Arthur J. Prutzman K3DTL, 31 Maple- 
wood, Dallas, Pennsylvania 18612. All 
phases of ham radio. Can assist with pro- 
curement of parts, diagrams, etc. 

William G. Welsh W6DDB, 2814 Em- 
pire Ave., Burbank, Calif. 91504. Club li- 
censing classes and Novice problems. 

Ralph J. Irace, Jr., WA1GEK, 4 Fox Ridge 
Lane, Avon, Conn. 06001. Help with Novice 
transmitters and receivers and novice theory. 

Iota Tau Kappa Radio Fraternity W7YG, 
Multnomah College, 1022 S.W. Salmon St., 
Portland, Oregon 97205. This group of 
radio amateurs will answer any technical 
questions in the field of electronics. 



FEBRUARY 1968 



61 



Martin M, Hellman K2TAJ 

61 Scott Avenue 

Staten Island IO305 N. Y. 



A Grey Beard Writes 



It is possible that this will refresh the 
memories of some, and it may remind others, 
that the things they take for granted, did 
not happen yesterday or the day before. 

Occasionally, during a chat with someone^ 
on the air, the door opens for a look back 
to the old days, of wireless. There are still 
a few of us, who have sharp recollections 
of how it was. 

Sixty years ago, landline telegraphy was 
the best of all hobbies* It did not cost too 
much, and the idea of sending and receiving 
messages over a distance, via a single wire, 
gave us all quite a kick. If you could put 
together some simple parts to make a sound- 
er and key, and find some bell wire, and an 
old wet battery, you were in business. In 
our locality, as it is now, in many parts of 
the country, there was always the rich kid, 
who could afford to buy ready made gear* 
However, most of us had to improvise, in- 
vent, scrounge, hustle, and sweat, for the 
things we needed. We learned the code, 
the hard way. 

In the big city, lines usually ran from 
apartment to apartment, and across the 
street, to other buildings. I strung one line 
beneath an elevated rail structure , and up 
to the top floor of Smitty's house on the 
other side of the avenue. 

I earned money collecting and selling 
bottles to liquor stores, delivering race re- 
sult cards to the corner saloons, and was 
the general delivery boy for everyone. 

There was no such thing as asking Pop 
for money to buy apparatus, anyone doing 
so, was asking for the back of the hand. 
Many people were still scared stiff after the 
panic of 1907. The scare persisted for a long 
time, and anyone who could save, did so, 
in spades. It was a hard school, and a very 
thorough one. 

I visited the old neighborhood after fifty 
years 9 and could fine only two familiar names 
on the store fronts. The schools, the elevated 
railroad, the house I lived in, are all gone. 
The fire house is all that remains. 



I had a momentary feeling of sadness, and 
wished I could go back to those dear days. 
And to shake that dull feeling of being alone, 
I went into a local watering place and had a 
drink of leopard's milk. 

While resting my arm on the bar, I re- 
membered the five miles to Mesco, where 
the sales clerk used the telegraph key to 
talk to people in other part of the store; 
and the Electro Importing Company at 233 
Fulton Street. If you wanted anything in the 
telegraph, wireless, or electrical line, such 
as wire, tubing, sliders, binding posts, ear 
phones, castor oil for the special variable 
condensers; these two places had the stuff. 

If you wanted to go downtown to buy 
or browse, you either walked, or hitched a 
ride on the rear of a brewery truck. Any 
money you had ? was for more important 
things than transportation. 

The causes of landline telegraphy going 
out, and the new art of wireless coming in, 
were, a magazine called "The Electrical Ex- 
perimenter", and the catalogue of the 
"Electro Importing Company." That cata- 
logue was a masterpiece of descriptive liter- 
ature. It was filled with choice items, such as 
coherers, electrolytic detectors, tuners, wire, 
loading coils, galena, iron pyrites, and some 
marvelous looking receiving sets. 

Books on the new art, were non-existent, 
and we gathered our ideas and knowledge 
from reading those two articles. For code 
practice, we listened to the Navy stations, 
and the few commercial stations, 

I was impatient and wanted to go farther 
and faster in wireless. I first tried Western 
Union, but was turned down for some rea- 
son , I still haven't been able to figure out. It 
is ironic that they hired me as a relief 
operator at the local Maritime Observatory, 
at Quarantine, fifty years later. They needed 
a blinker operator, 

I found a job at DeForest's plant, which 
was located on the Harlem River, near 
Highbridge. My job was sweeping up, and 
cutting wires to length, with an old paper 



62 



73 MAGAZINE 



cutter, I did not stay long in that fob, it was 
too confining, and besides, I wanted to see 

everything that went on. 

The factory was in an undeveloped area, 
nothing but weeds and scrub trees surround- 
ing the place. This made it easy for some 
fellows to throw parts out the rear windows , 
and come back at night to pick up the stuff. 
The bolder ones would slip an ULTRA AU- 
DION panel under their shirts, and sneak it 
out during lunch hour. 

Our parents were very strict, and we all 
knew the penalty for bringing home any- 
thing, without a good explanation of it's 
origin. Anything that smelled of thievery, 
meant a walloping, 

One day, I scraped together six dollars , 
and bought a vacuum tube, with pigtails 
coming out both ends. It lasted three hours, 
and while it lasted, the gang came to my 
house at night to listen for recorded music 
sent out by DeForest's station. He was per- 
mitted to transmit music, after 11 p.m. and 
for a distance no further than 27 miles. 
Which was just the distance from New York 
to Ossining ? where his engineer lived and 
worked. The one thing that annoys me now, 
is that I can't remember his name. The name 
Gowan, rings a bell, but I can't be sure. 

From 1907 to 1924, more and more peo- 
ple worked on wireless research and devel- 
opment, DeForest held U. S, patent #879,- 
532 filed Jan. 29, 1907, and British patent 
#1427, filed Jan. 21, 1908, for the third 
electrode in a vacuum tube, which was 
mounted between filament and plate. As a 
result of this invention, direct wire telephony 
from New York to San Francisco was suc- 
cessful in 1914. 

DeForest, Armstrong; and C, S. Franklin 
and H. J # Round, of England, worked on 
the discovery that a vacuum tube had os- 
cillating properties. 

Speech was transmitted from Arlington, 
Va., to Paris and Honolulu in 1915. The sta- 
tion used about 300 tubes, rated at 25 watts 
each, as oscillators, modulators and power 
amplifiers. 

Armstrong developed a system for re- 
ceiving radio signals in 1919, and he called 
it a Superheterodyne. Three years later he 
came up with Superregeneration. 

C. W. Rice and L. A, Hazeltine, in 1920 
and 1924, respectively, found ways to stop 
unwanted oscillations. 

Finally, W. Schottky installed a second 



grid in a vacuum tube in 1919, and we 
know this as a screen grid. 

If you attended the Radio Show at the 
Grand Central Palace, just before Xmas 
1922, this is what you saw. A fine assort- 
ment of spark and arc transmitters; a new 
type of transmitting condenser by Dubilier; 
demons trations of superregenerative receiv- 
ers with loop antennas; iron core rf trans- 
formers; and some new ideas in synchro- 
nous rotary spark gaps. 

Today, you can hit Fop for a few hun- 
dred bucks and rush right down to the 
nearest radio store, and buy a beautiful 
piece of gear, a half gallon or so, wheel it 
home in a taxicab, load up a brass door 
knob and you are a "HAM". 

. . , K2TAJ 



±llllll[llHJIIIIIIIIIllll||||l|||||tlllMllllllllllirillill]IIIItlilllIIIIII1ll[|l|MHIIIIIIMIIIIIIl!IIII]MI]lll!IIJI^ 

f 2000 ARTICLES? 

3 = 

| In the 75 issues of 73 between October I960 | 

| and December 1966, over 2000 articles have | 

| appeared. Find the ones you want quickly with | 

| our NEW six year cumulative index. It lists | 

| all articles by subject in easy-to<find form. | 

| The index Is available now. Index 25* | 

| 73 Mo go line Peterborough, N, H. 03458 I 

— s 

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616J Tube w/ Connectors. 100 watts to 1200 mc, 
R443/ARN5D Receiver w/6 Xtals and 11 Tubes. 
T465/ALT7 100W Xmlttr. 108-352mc w/2-6161s 
ID9IB/ARN6 Bearing Indicator for ARN6 Becvr, 
AS3I3B/ARN6 Station Seeking Loop. 100-1750 kc. EX 6.25 
RT3I6/APNI2 160-234me Transceiver w/tubei EX 12,50 

[DI69C/APNI2 Scope. 3JP1 CRT. DPDT Coax Switch EX 9.75 

OAA-2 150-24Gmc Teat Set. 115V 60cy Supply EX 14,75 

AM300 Tnterfone Amplifier w/pp 6AQ5's output EX 4.75 

Cabinet, Slope Front w/3 Meters (15, 25, 50ma) ..EX 7.50 
AT339/PRC 37~55mc Hand Held Loop w/cord. Bag EX 12.50 

PP336 Main Power Supply Tor APB9 Receiver EX 16.50 

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1D226/APR9 Panoramic Indicator w/schematic . .,.EX 14,50 
SN36B/APS31 5-807% 46 other tubes, 2 blowers ..EX 9.25 

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R3I6A/ARR26 14-Tube 162-174mc AM/FM Superhet 22.75 
PP468 Power Supply for R316A Receiver, 400cy. , ,LN 4.75 

C6I0 Control Box w/4 tubes for R316A Recvr, EX 4.50 

Adaptor connects PL250 to BNC Panel Socket ...LN3/1.75 

OH MITE Z-50 RF Choke ...EX 6/1.00 

Scope Xformer 19S0V@3ma, 5 Ml windings, 60 cy NEW 4.75 

SA325/U Coaxial Switch, SP4T. 28VDC Motor EX 6.50 

Coax Switch. DPDT. Thompson Prod, No. E1SB22CA LN 4.25 

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Battery Charger 115Y60cy to fiVDC # 20ampa ..NEW 9.75 
Panel w/15 Leach 24TOC Relays. lOamp 3PDT NEW 6.50 
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Prices; FOB Bay Saint Louis. Terms: Net, Cash. 



FEBRUARY 1968 



63 



The Quartenna 



Bill Krause WA60BH 
1616 Roselawn 
Stockton, Calif 95204 



In my opinion, and that of many other 
hams, Im sure, the Heathkit Cantenna is 
one of the best ham test equipment bar- 
gains on the market today. Its popularity 
is obvious from the number of articles pro- 
pounding its virtues or suggesting modifi- 
cations to further enhance its usefulness 
that have appeared in ham publications 
in the past few years. I would like to offer 
here a "modification" that will remedy 
what I feel is the Cantenna's greatest draw- 
back—its size. 

For those of us who run a full gallon 
to a rig complete with VOX, phone patch, 
antenna switching, and nice, neat hidden 
cabling, a Cantenna on the floor behind 
the operating console is the answer to the 
tuneup problem . But what about those of 
us who run a small transceiver set up on 
the kitchen table, or what about the VHF 
experimenter whose bench is already three 
feet deep with the latest project? For these 
hams the Cantenna is large— in fact, four 
times as large as it needs to be. The cate- 
gory I fall into is that of a VHF experi- 
menter. As with most VHF operators, (we'll 
ignore the moonbounce and tropo scatter 
boys) I seldom have more than fifty watts 
of rf to handle from any one piece of 
equipment. It was with this need in mind 
that I came up with the Quartenna. 

The Quartenna is essentially a 50 ohm 
nominal resistive element mounted in an oil- 
filled quart paint can. The resistive element 
is made up of ten 510 ohm 2 watt resis- 
tors connected in parallel to provide a 51 
ohm load. Either a resistor value of 470 or 
510 ohms is sufficiently close to the 500 ohm 
value which would make a perfect 50 ohm 
load. (I used 510 ohm resistors because my 
favorite surplus dealer has them for three 
cents apiece.) As can be seen from the 
photograph, the resistors are mounted be- 
tween two 1%" copper discs in a IK" 
circle. This spacing allows the cooling oil 
to circulate between the resistors. Be cer- 
tain to maintain at least Me" clearance be- 




tween the resistor bodies and the discs; this 
minimizes the mechanical stress and strain 
on the resistors caused by heating and cool- 
ing- The center of the bottom disc is drilled 
to accept the center conductor of the co- 
axial support. The top disc is drilled and 
filed out to &" to accept the outer con- 
ductor of the coaxial support. The support 
conductor sizes were chosen to provide a 
characteristic impedence close to 50 ohms. 
In my unit I used a short length of RG- 
17 /U coax with the insulation (both inner 
and outer) removed and with the ends of 
the shield braid tinned to help it hold its 
shape. If you use tubing for the outer con- 
ductor, drill a small hole near the end that 
mounts to the end of the can. This will 
keep the oil from being forced out the coax 
connector. The top end of the center con- 
ductor is drilled to accept the center stud 
of the coax fitting. The connector I used 
is a single hole mount UHF fitting, A screw 
mount fitting should work as well The cen- 
ter of the lid of the can is drilled to accept 
the coax fitting. 

Begin assembly by soldering the resistors 



64 



73 MAGAZINE 



between the two discs. Next solder the coax 
fitting to the lid of the can. Solder the cen- 
ter conductor to the center stud of the fit- 
ting, being careful to keep the center con- 
ductor perpendicular to the plane of the 
lid. Solder the outer conductor to the lid 
after centering it around the coax fitting 
and making sure it is perpendicular. Slip 
the assembled resistors and discs in place 
and solder the upper disc to the outer con- 
ductor and the lower disc to the inner con* 
ductor. Fill the can to within about 1" of 
the top with oil 

Transformer oil is superior, but salad or 
motor oil will work. Put the lid on the can, 
give the outside a coat of flat black paint, 
and presto! 

Results: I must say that the results were, 
at the least, quite gratifying. Some of you 
are probably wondering why no vent in 
the can for leaking oil as the Cantenna has. 
Well, a unit of this simplicity can't have 
everything! Seriously, I found that the load 
"breathes" through the coax fitting and 
there is no problem of pressure buildup. 
If you use a fitting which is sealed, a vent 
will be necessary. The VSWR of the unit 
measured as follows: 4 MHz, 1.05:1; 30 
MHz, 1.05:1; 50 MHz, 1.05:1; 144 MHz, 
1.08:1. The reactance at 44 MHz is capaci- 
tive. The unit was tested at 50 watts rf 
for thirty minutes. At the end of this period 
the can was not too warm to hold and the 
resistance of the element had drifted up- 
ward only 0,5 ohms. After operating at 50 
watts for thirty minutes, the power input 
to the load was raised to 200 watts for five 
minutes. The can was still not too hot to 
hold and the resistance of the element had 




drifted upward only 1 ohm. I think you 
can see what I mean by "gratifying". It 
appears to me that the Quartenna should 
handle 50 watts continuously or 200 watts 
RMS or 400 watts PEP on an intermittant 
basis. 

Suffering from cramped quarters or a flat 
pocketbook? Need a good dummy load? 
Then whv not shell out about three bucks, a 
few feet of solder, a pleasant evenings 
work, and build yourself a Quartenna? 

My thanks to WA6IHX for his help with 
the photography. 

. . . WA60BH 



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FEBRUARY 1968 



65 



Bob Eldridge VE7BS 
805 East 20th Avenue 
Vancouver, British Columbia 

Canada 



Hydronics or Radio? 



In the May 1966 publishorial Wayne Green 
made brief mention of the reports from Sara- 
sota, Florida on the probable existence of 
a new form of radiation termed, for want 
of an existing word, hydronics . Just a year 
later, in the May 1967 Radio-Electronics, an 
article appeared which described practical 
experiments in the new form of underwater 
communication. In the 1966 Proceedings of 
the Joint Technical Advisory Committee 
(IEEE/EI A) there are several references to 
hydronic radiations and a considerable 
amount of memoranda on the subject* 

I do a lot of reading, For the benefit of 
those who do not, I thought it might be 
interesting to go over some of the argu- 
ments and add a few of my own. The people 
at Sarasota say that most of the conventional 
explanations of their results have been ad- 
vanced by scientists who have not witnessed 
the full gamut of such demonstrations. I 
haven't seen any of their demonstrations, 
so the only thing that doesn't drop me right 
into the group of explainers is that I am 
not a scientist either. Fools step in. < . 

But hams have uncovered things that sci- 
entists have overlooked, and real results are 
sometimes achieved from persistent seren- 
dipity (the process of talking and talking 
and talking about something until eventually 
a fundamental truth pops out that none of 
the talkers was aware of originally). So 
much for my unqualifications to discuss hy- 
dronics. If you aren't interested in my own 
observations, just ignore the paragraphs in 
italics. 

What is it all about? 

There must be somebody who hasn't 
heard of hydronics, so let's go over the 
basics briefly. It has been discovered that if 
a pair of special antennas are submerged 
in water several miles apart, an AM signal 
can be sent from one to the other. If the 
antennas are brought closer to the surface, 
the signal increases; if they are brought 



above the surface, the signal disappears or 
is greatly reduced. If one antenna is left 
below the surface, communication is possible 
with certain other types of antenna above 
the surface and at a distance. Communica- 
tion can be achieved over a distance greater 
than that predicted by the normal electro- 
magnetic radiation formula used to show 
the attenuation expected on an underwater 
path. 

From this, the proponents of the "Hy- 
dronics Theory" deduce that there is a form 
of radiation from the transmitter somewhat 
different from electromagnetic radiation, 
possibly a form of energy heretofore not 
proven to exist, although hypothesized by 
some of the early experimenters in radio 
and electricity. 

This becomes interesting to the JTAC 
subcommittees because the thought rears its 
ugly head that besides all the pollution of 
the radio spectrum by the emissions we 
already know about (No, not the VOA in 
the 7-MHz band!), there may be a whole 
slew of emissions using the same frequencies 
but of a different nature. Can't you just 
hear the groans of the landlubbers being 
echoed by resounding cheers from the naval 
types! 




INSULATOR 



METAL 
PLATE 



L"6" FOR THE BATHTUB 
6'0" FOR THE SEA 



Fig. L Underwater dipole for studying the effects 
of underwater radio transmission. For bathtub ex- 
periments the dipole can be about 6 inches long; 
for ocean testing six feet is preferred* 



66 



73 MAGAZINE 



Practical details 

Typical antennas are short dipoles with 
flat plates at the ends, center fed with an 
insulated balanced feeder (see Fig, 1). For 
simple experiments in a bathtub, Jack Alt- 
house's article 1 shows a simple one-transistor 
oscillator modulated by a one-transistor tone 
generator. There isn*t any magic claimed 
for the gear, but it is easier to build some- 
thing like that than it is to figure out a 
way to modulate your VFOI 

Bathtub antennas can be any size you find 
convenient. The longer they are and the 
larger the endplates, the stronger will be 
the radiation. If you go whole hog and do 
it in the sea, try 6-foot dipoles with plates 
one foot square, and do it on 160 meters. 
If you use a full-scale transmitter you will 
need some walkie-talkies or something for 
"order- wire" because the transmissions will 
go a long way. Very low power and furious 
waving of arms or shouts works out to be 
more convenient in the long run. Go QRF. 

No magic about the receiver either— any- 
thing that will receive on the frequency, 
detect the modulation, and couple to a dipole 
will work. If it isn't screened, you may 
have some perplexing results! 



RADIO 



HVDRONICS ? 




•: : j: : .-: ■:■:::.■■■ .-. ■ ■■ .:.?> 



Pig, 2» Do the signals travel above or below the 
sea-air interface? 

Experiment I 

Two antennas are immersed in the ocean, 
100 meters apart. Each antenna is a 6-foot 
dipole with metal end plates, A signal trans- 
mitted from one antenna to the other is 
found to be maximum when the antennas 
are in line with each other, minimum when 
they are broadside. Fig. 2. Sarasota says, 
"With radio waves, maximum signals would 
be received when the transmitting and re- 
ceiving antennas are broadside, and a mini- 
mum signal when they are coaxial." 

Although everyone remembers that the 
maximum lobes of horizontally polarized 
waves are at right angles to the wire of 
a horizontal dipole, many people forget that 
the maximum vertically polarized waves are 



emitted from the ends, Fig. 3. If you con- 
sider for a moment that this might be 
normal radio propagation, you will agree 
that horizontally polarized waves would not 
travel far across the surface of land or 
water before being attenuated by the short- 
circuiting effect of the horizontal surface. 
So, along the lines of, "if it's radio, it would 
have to be vertical polarization", we would 
expect the antennas to be end on to each 



Experiment 2 

The receiving antenna is replaced by a 
single plate. The transmitting antenna is 
rotated and it is found that the signal is 
at a maximum when the transmitting an- 
tenna is end on. Communication ceases when 
either or both antennas are removed from 
the water. 

Experiment 3 

The antennas are exchanged end for end. 
The dipole shows the same directivity when 
used as a receiving antenna. Communication 
ceases when either or both antennas are 
removed from the water. 

Let us assume that a radio emission has 
emerged from the water at a point close to 
the transmitting antenna and then travels 
along the surface as a vertically polarized 
wave. The receiving antenna, when removed 
from the water, would only respond to the 
wave if it has the capability of receiving 
signals from a horizontal angle. Although a 
horizontal dipole transmits or receives ver- 
tically polarized signals off tiie ends, this 
is almost all high angle radiation. This is 
one reason you work so well off the ends 
of your 40-meter and 8Q-meter horizontal 
dipole— it surprises many hams, but it 
shouldntl 

From the description of the experiment 
it seems that tlie single-plate antenna 
(termed a monopole) consists of a plate 
perpendicular to the water surface and fed 
by a single horizontal wire. It would be 
interesting to know whether a vertical stick 
monopole above the water would receive 
the signals that the vertical-plate~on~a-tcire 
could not. See Fig* 4. 

Experiment 4 

Two monopole antennas are used. Both 
act omnidirectionally. Communication ceases 



FEBRUARY [968 



67 



when either or both are removed from the 
water. 

Experiment 5 

A dipole antenna below the surface trans- 
mits to "an antenna" above the surface. Ro- 
tation of each shows maximum signal when 
they are colli near. 

It is difficult to comment on this because 
it is not clear what kind of antenna is at 
the receiver. The same goes for Experiment 
6. 

Experiment 6 

A sealed transmitter with 0,1 watt output 
to a two-meter-long dipole antenna is lowered 
into 30 meters of sea water. A vertically 
disposed dipole just below the surface is 
connected to a receiver. Measurements show 
that as vertical distance between the an- 
tennas is varied, the attenuation varies as 
the square of the distance. Similar experi- 
ments in a horizontal plane, with the an- 
tennas end on, give the same results at 
the same distance. 

This only shows that if the signal travels 
through the water all the way, water has 
the same conductivity in one direction as 
in another. If we consider the signal emerges 
from the water, travels horizontally across 
the surface of the water in the air, and 
returns part of its energy to the water 
continuously as it travels along, then Experi- 
ment 7 is not of much interest, as it only 
proves what we already know— that water 
is a rather poor medium for the internal 
propagation of radio waves. 

Sarasota says, "The attenuation of a 6-kHz 
radio signal after traversing 100 meters of 
sea water is about 250 dB, To receive a 
signal over that distance on a receiver with 
a sensitivity of 10 ~ 9 watts would require a 
transmitter power of 10 61 watts . . . Since 
the power required to transmit a radio sig- 
nal under these conditions is so great, it is 
unthinkable to ascribe these phenomena to 
conventional radio waves/* 

But what if the signal goes a few meters 
through the water, best part of 100 meters 
through the air, and then into the antenna 
through another short water path? There is 
plenty of literature supporting the theory 
that if a radio signal passes through an 
interface between two media of radically 
different density, the signal will be refracted 
along the surface of the interface. Stairnan 



and Tamir 2 say that the only necessary con- 
dition is that the signal must arrive at the 
interface at the critical angle. As the signal 
travels along the surface of the sea, in the' 
air, it constantly returns a portion of Us 
power to the sea, entering the surface and 
propagating downward at the same critical 
angle. It will be intercepted by a receiving 
antenna below the surface. 

If you have forgotten your high school 
physics, fill a glass with water and hold a 
knife blade in the water, entering at an 
angle of 45° or so. View the blade from 
various angles looking down into the water, 
and the knife will appear to be bent. This 
is optical refraction. If you have ever tried 
to spear a fish from a boat you will already 
have learned about this tJie hard way! 

So now we have a possible explanation 
for the underwater communication. The 
heavily end-loaded horizontal dipole radiates 
vertically polarized waves off the ends 
towards the surface of the sea at such an 
angle that when the wave emerges from 
the surface it is refracted to the horizontal 
It then propagates over the surface of the 
sea. The attenuation over the main portion 
of the path is that of a surface wave in 
air over a good conducting layer. All the 
way along the over-water path, part of the 
energy of the wave front is fed down into 
the water, entering the water at the same 
critical angle which gave rise to the propa- 
gation of the wave t Stairnan and Tamir 
go into an extensive dissertation on the 
features of the lateral-wave component of 
the surface wave. This gets a bit deep even 
for those hams not unhappy about the pro- 
visions of the new incentive licensing law. 





(a) 



(b) 



Fig* 3* The directional pattern of a short horizontal 
dipole is shown in A [horizontally polarized waves]. 
Directional pattern of a short horizontal dipole 
showing the high-angle vertically polarized waves. 

So What? 

So what conclusions can we draw from 
tliis? Anyone who sticks out his neck by 
drawing positive conclusions has courage. 
But at least there is good reason to believe 



68 



73 MAGAZINE 



that the scientific world will continue to 
be skeptical about the existence of a new 
form of energy until considerably more de- 
tail has been published of controlled tests. 
It would be very interesting to make 
some tests on UHF or microwave over a 
very short path and see what happens when 
a metal plate is suspended first in the air 
and then in the water at the mid-point of 
the path— or is that too simple a way to 
determine where the wave is travelling? 

Signals from fish 

Sarasota Research & Development also 
reports some very interesting experiments 
with fish. One hundred thirty species have 
been studied, and they all emit signals re- 
ceivable on an electronic receiver. Each kind 
of fish can be identified from the character 
of the signal. For example, sea robins trans- 
mit short pulses at 170 Hz, black drum 
transmit on a carrier frequency of 6.5 kHz, 
and pinfish on 28 kHz, 

The part of the fish said to give rise to 
the omissions is the skin surface along the 
lateral line. The skin transmits a signal 
even after having been separated from the 
rest of the body, and radiations have been 
monitored 100 meters away from the fish. 



^•o 



AIR 

SURFACE WAVE 



VERTICAL 
RESPONSE 








-•X- -- 



Fig. 4. An antenna with maximum response at a 
high angle might work fine under the water, but 
pretty poorly above it- 

Who needs transmitters? 

Another interesting report is> that using 
a dipole with end plates of dissimilar metals 
immersed in sea water, radiations are emitted 
from the antenna even when no transmitter 
is attached! Yet a VTVM with an input 
impedance of 10 14 ohms connected across 
the feed point of the dipole shows no po- 
tential gradient to exist. One of the plates 
was of zinc and the other of copper, and 
the signal was receivable 100 meters away- 



So there you are. Undoubtedly there are 
some very interesting things going on in 
Florida, and before long there may be some 
new electronic aids for fisherman, and for 
divers. Whether it be hydronics, plasmonics, 
or just plain old radio, the search for better 
communication goes on. And, I guess, so 
will the argument. 

. . . VE7BS 

References 

1. J. Althou.se> "Build Hydronic-Radiation Transmitter," 
Radio- Electronics, May 1967 f page 37. 

2. Staiman and Tamir, "Nature and Optimization of 
the Ground (Lateral) Wave Excited by Submerged 
Antennas," Proceedings of IEEE, Yolume 113, Number 
8, August 1966. 



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FEBRUARY 1968 



69 



Roy A, McCarthy, K6EAW 
737 W, Maxiim Ave. 

Fuller+on, California 92632 



Electronic Temperature Measurements 



Frequently in electronic work it is nec- 
essary to determine the temperature rise of 
components located in areas that are in- 
accessible. When use of a thermometer is 
inconvenient or impracticable, in industry 
we generally turn to thermocouples and po- 
tent iometric recorders. Alternately, therm- 
istors can be used, if the curve of resistance 
vs, temperature is available. These can be 
purchased for around $5.00 from Allied 
Radio, An accurate meter to measure the 
thermistor is to be desired. 

For the single shot type of temper ature 
measurements the average amateur is likely 
to encounter, such as determining the temp- 
erature rise of a TV transformer used in 
a home-built transmitter, or the temperature 
rise in the compartment of a VFO where 
installation of a temperature compensating 
capacitor is contemplated, there is a far less 
expensive method. This involves very simple 
calculations based on the change in resist- 
ance of copper wire as its temperature is 
raised. Since these are relative resistance 
measurements absolute accuracy is not re- 
quired. The percentage change is the im- 
portant criterion. Hence an ordinary ohm- 
meter can be used providing it gives re- 
peatable readings and is used on a scale 
where changes of 20 to 50 percent can be 
readily recognized. 

Let's take the transformer discussion first. 
Ordinary type commercial transformers use 
Class A insulation and should be limited 
to about 212° Fahrenheit or 100° Celsius 
(formerly called Centigrade). The ambient 
or room temperature plus the temperature 
rise should not exceed this value. In case 
you Ve forgotten, to go from degrees F to 
degrees C; simply subtract 32 then divide 
by 1.8 (or multiply by 5/9 if it seems 
easier). Now then, copper which has been 
annealed, like soft drawn magnet or trans- 
former wire, has a temperature coefficient 
of resistivity of 0.00393, so each ohm of it 
will increase 0.00393 ohms for each degree 
C of temperature rise. This isn't perfectly 



T = 255 



-I 



linear of course, but is accurate enough for 
all practical purposes. By juggling a few 
figures > or checking a reference book, we 
find that the temperature rise of the trans- 
former winding will be; 

( R hot 
R cold 

So, the procedure is to simply measure 
the tranforrner primary resistance when it is 
cold, watching out for parallel circuits that 
might cause false readings. Then operate as 
usual for the maximum expected time* If 
you use CW, don t lock the key down. Then, 
at the end of the session, again measure the 
primary and calculate the temperature rise. 
Add this to the room temperature. This tells 
you the temperature inside the transformer, 
where it counts. 

It may be of course, that some will in- 
sist on more accurate measurements, since 
the transformer did cool down somewhat 
between the time power was disconnected 
and you got around to checking it, Lets say 
it took one minute. Then at one minute 
intervals take several more readings, Draw 
a simple graph and plot it back to time 
T = (X This gives the actual hot resistance, 
The graph will be nearly linear and a 
smooth curve easy to plot. 

To calculate the required temperature 
compensating capacitor to use in parallel 
with the tuning capacitor to compensate for 
drift; we must find the temperature rise 
in the area of the enclosure where the TC 
is to be located. A simple sliderule is avail- 
able for only 18 cents to perform the cal- 
culations. (Allied 19U916). To find the 
temperature rise, suspend a tiny transistor 
interstage transformer in the VFO. Don't 
let it touch the chassis. A tiny one should 
be used to insure that it will have a short 
thermal time constant. This is necessary if 
we want to follow the changes in the air 
temperature. As with the power trans- 
former, measure the coil resistance when it 
is cold, and as the equipment goes through 
its warm-up cycle. Then calculate the temp- 
erature rise as indicated for the power 



70 



73 MAGAZINE 



transformer. An important difference; do 
not add the room temperature. The Q C 
rise is all that is required for calculating 
the change in capacity of a TC capacitor. 
If you don't feel like spending the 18 cents 
for the calculator, you can always figure 
that for small changes in capacity, the fre- 
quency shift is nearly linear, and work it 
out from there. 

Since two other methods of temperature 
measurement were also mentioned as a 
teaser, a brief discussion of them might he 
in order. Allied Radio has, in their In- 
dustrial Catalog, a one percent accuracy 
thermistor, with curve, for about 5 dollars. 
Or, in their wishbook for Everyone, they 
have a kit of 4 glass beads (thermistors), 
probes, manual, and curve computer for 
the same price. Discs are less than a dol- 
lar, but you calibrate them yourself. 

In using thermistors at least two precau- 
tions are necessary. First of all the measuring 
instrument must not supply appreciable 
power to the thermistor, or else self -heating 
effects will nullify the calibration. Second, 
with beads, remember they have a very 
short time constant, the same as many 
other semiconductors. In other words, they 
blow out faster than they can be discon- 
nected. And, as was mentioned, the tiny ones 
can get lost when you suddenly sneeze. 
See: Which Way is UP?. 73-Feb, '62. 

While thermocouples are widely used and 
simple to make, they have one great big 
disadvantage. The output is in the order of 
millivolts and the lead resistance is high. 
Hence, unless a very sensitive meter is used, 
the meter and thermocouple must be close- 
ly matched. Clip the leads short and the 
accuracy is gone. If a sensitive milli voltmeter 
is available, a conversion chart can be read- 
ily obtained which will give accurate temp- 
erature readings. This permits making sev- 
eral simultaneous measurements in a chassis 
by switching in numerous thermocouples. 
Leeds & Northrup Co, (see the yellow 
pages) has a conversion table booklet at a 
very nominal price, like free. That is, if 



you can convince the person who answers 
the phone that you do a lot of such work. 
These conversion tables are generally based 
on using a reference thermocouple at 32° 
F or 0°C. This requires icy slush, and can 
get messy. Of course the chipped ice can 
be used for cooling other stuff which may 
help pass the time during the temperature 
run. 

With a small VFO, you may be able to 
sneak it into your place of employment, or 
have a good friend take it in and check 
it for you, doing the measurements with pro- 
fessional equipment. Most industrial elec- 
tronic and chemical plants make consider- 
able use of temperature measurements ob- 
tained by thermocouples and recorded or 
indicated on potentiometric recorders. The 
recorder is generally a bridge circuit which 
is balanced by a servo mechanism driven 
by the error signal from the bridge. At bal- 
ance, the voltage from the thermocouple is 
matched by an equal but opposite voltage 
from the recorder. The net result is an 
apparently infinite input impedance, so the 
thermocouple is not loaded and the length 
and resistance of the leads is of no con- 
sequence. This isn't really true of course, 
since at balance we wouldn't know if the 
reading is steady or the recorder dead. A 
little jitter is generally added to make things 
look alive. Far off balance the recorder in- 
put impedance may be IK ohms or less. 
But the readings there are, of course, un- 
important- Of importance is the fact that 
up to 12 automatically switched inputs may 
be available, allowing one to locate thermo- 
couples all over the VFO chassis to find 
the hot spots. And a continuous recording 
helps to tell what causes the frequency to 
drift back and forth. No ice bath is re- 
quired in most set-ups since automatic temp- 
erature compensation is generally included. 

Other temperature sensing elements, such 
as diodes and transistors are available. For 
simplicity, the copper resistance method is 
hard to beat. For economy, it can not 
be beat. 

. . . K6EAW 



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Propagation Chart 



FEBRUARY 1968 



J. H, Nelson 



EASTERN UNITED STATES TO: 





CUT: 


00 


M 


iH 


M 


05 


ifl 


. _ 


14 


16 


if 
■ 


20 


■ 


3 


A u A J f« A 


It 


14 


T 


7 


7 


7 


T 


7E- 


14 


l\ 


21A 


It 


ARGENTINA 


21 


14 


14 


7A 


7 


7 


14A 


:•: \ 


21A 


21A 


28 


as 


AUSTRALIA 


21A 


14 


TB 


7B 


7B 


7B 


7B 


14 


14 


14 


21 


m 


CASAL 2 ONE 


2 2 


14 


7 


7 


7 


7 


14A 


21A 


28 


u 


28 


21A 


ENGLAND 


7 


7 


: 


7 


7 


TB 


24 


21A 




21 


14 


14 


HAWAII 


31 


14 


7B 


7 


7 


T 


T 


,7 B 


14 


21A 


21A 


21A 


INDIA 


7 


7 


IB 


7B 


?B 


TB 


14 


21 


u 


7B 7B 


to 
i 


JAPAS 


14 


14 


MB 


TP 


TB 


7 


: 


- 


7B 


7B 








7B 


14 






MEXICO 


21 


14 


7 


7 


7 


T 


T 


14A 


21A 


n\ 


21A 


21 


PHILIPPINES 


14 


14 


145 


TB 


TB 


7B 


TH 


14 


14 


I4F 


7B 


14 H 


PUERTO RICO 


14 


7 


7 


7 


7 


7 


14 


MA 


I1A 


21A 


21 


14 


SOUTH AFRICA 


14 


14B 


T 


7B 


TB 


14 


21A 


2ft 


29 


n 


aiA 


21 


U. S* fi. R. 


| 




7 


7 


7 


TB 


14 


21A 


21 


14 


7B 


711 


WEST COAST 


2! 


u 


7 


7 


7 


7 


7 


14 


21A 


21A 


2B 


1U 




CENTRAL UNITED STATES TO: 





ALASKA 


21 


14 


7 


7 


7 


7 


7 


7 


14 


21 


21A 


21A 


ARGENTINA 


21 


14 


14 


7 


7 


7 


14 


21A 


ilA 


21A 


29 


2ft 




AUSTRALIA 


2ft 


21 


14 


7B 


7B 


7B 


TB 


14 


14 


14 


21 


21 A 


CANAL ZONE 


21 


14 


7 


7 


7 


7 


14 


21A 


28 


28 


2B 


28 


ENGLAND 


7 


7 


7 


7 


7 


7 


14 


21 


21A 


21 


14 


73 


H A W A 1 1 


21A 


21 


14 


7 


7 


7 


7 


7 


14 


21 


2H 


21 A 


INDIA 


UB 


14 


7 A 


7 P. 


71 


7B 


7B 


14 


14 


14B 


14H 


14 


JAPAN 


21A 


14 


MB 


7B 


7 


7 


7 


7 


7 


7B 


14B 


21 


MEXICO 


14 


14 


7 


7 


7 


7 


7 


14 


21 


21 


21 


21 


PHILIPPINES 


21 


14 


MS 


7B 


TB 


TB 


7B 


Mr 


14 


14 


713 


14 


PUERTO RICO 


21 


14 


7 


7 


7 


7 


14 


21A 








21 


21 A 


2IA 


21A 


SOUTH AFRICA 


14 


14 


UB 


14E 


7B 


TB 


14A 


21A 


21A 


21A 


21 


21 


L . 3 .. S . H . 


7 


7 


7 


7 


7 


7B 


14B 


14A 


14 


14 


7B 


7B 




WESTERN UNITED STATES TO: 




ALASKA 


21 


21 


14 


7 


7 


f 


7 


7 


14 


41 


21A 


21A 


ARGENTINA 


21A 


21 


H 


14 


14 


T 


7 


14 


21A 


21A 


21A 


2ft 


: AUSTRALIA 


3B 


2a 


21A 


14 


14 


T 


T 


7 


14 


14 


31 


2IA 


CANAL ZONE 


28 


21 


14 


7 


7 


T 


7 


L4 


21A 


28 


23 


2i 


ENGLAND 


7E 


fl 


7 


7 


7 


7 


TB 


7B 


14A 


21 


14 


7R 


HAWAII 


28 


26 


21 


14 


TA 


T 


7 


7 


14 


21A 


2- 


2a 


INDIA 


14 


21 


14 


TB 


7B 


7B, 


TB 


70 


14 


14B 


Mr- 


14B 


JAPAN 


23 


21 


14 


7A 


7 


7 


T 


7 


7 


7B 


143 


11 


MEXICO 


21 


14 


7 


7 


7 


7 


7 


7A 


214 


21 


21 


r 

2 1 


PHILIPPINES 


21A 


21A 


14 


14B 


7B 


7B 


7B 


7 


7 


14B 


71 


14 


PUERTO RICO 


2IA 


H 


14 


7A 


7A 


" 


7 


14A 


21A 


28 


: : 


2ft 


SOUTH AFRICA 


14 


14 


7 


TB 


7B 


TB 


tt 


14 


21 


21A 


21A 


21 


u. s. a. R. 


TB 


-z\ 


7 


7 


7 


7F 


7B 


TB 


14 


14B 


7B 


7t; 


EAST COAST 

1 i - 


2] 14 


7 


7 


( 


7 


7 


14 


2: \ 


21A 


28 


21A 



Zip 17070 



A - S'ext higher frequency may be useful, 
B - Difficult circuit Hit* period. 



Good: 1. 2, 7-11. 13, 14. 16-18, 25. 26, 28. 
Fair: 3, 4. 6. 12, 15. 19, 20, 22, 24, 27 
Peer: 5, 21, 23 
VHF: 2, 3, 9-11, 13, 27, 28, 29 



29 



72 



73 MAGAZINE 



(WIEMV from pg. 2) 

ones. We have broadcasts of music, hate mes- 
sages designed to create racial riot, obscene 
language, and wild drunken parties. The as- 
sumption is that these are amateur operat- 
ors who don't care about their tickets any- 
more. But, assuming that they are intruders 
who have taken, this means to give amateur 
radio a black eye, we still have a long way 
to go to clean house. 

We keep talking about the problem of at- 
tracting new hams. The idea being that the 
more hams we have, the better our chances 
will be of keeping our share of the radio 
spectrum when (and if) there is another 
frequency allocations conference. However, 
our choice of newcomers should not be in- 
discriminate. Before vou "sell" our hobbv to 
a casual acquaintance, look at him with an 
objective eye. Is he (or she) a normally 
courteous person? Is he the kind of person 
you would like to work side-by-side with 
on the same band? If not, don't encourage 
him to join the hobby, From a psychological 
view, there are some people who will use 
ham radio to make like a "big shot", and no 
amount of incentive legislation will change 
a basic personality defect. Let's attract the 
people who will be an asset to the hobby 
and fight to keep the others out. 

Many of our readers have expressed the 
opinion that the amateur exam (even the 
General) is too hard. The code should be 
eliminated so they could pass the exam, etc, 
I began working for the General license 
when my kids were still young and required 
lots of my time, I set a goal for myself to go 
from knowing nothing about code or theory 
to the General in a period of four months. 
I made it, but it was hard work under try- 
ing circumstances, I think my license means 
more to me because I had to work for it. 
I don't want to see the requirements lowered. 
This would only bring in more people to 
whom the hobby is simply a lark and the 
license unimportant, 

. , . WIEMV 



YOUR CALL 

Please check your address [abet and make sure 
that it is correct. In cases where no call letters 
has been furnished we have had to make one up. 
If you find that your label has an EE3*&* on it 
that means we don't know your call and would 
appreciate having it. 



Listen for the hundreds of 
LK-2OO0 Imeors now on the 
air and judge for yourself. 
Write for free illustrated 
brochure or send $1,00 for 
technical and instruction 
manual* 



BTI AMATEUR DIVISION 



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LINEAR 
AMPLIFIER 

For SSB, CW, RTTY 

Maximun legal input 

Full loading SO-IOM 

Rugged Eimac 3-lOOOZ 

Dependable operation 

Easy to load and tune 

No flat topping with ALC 

Distinguished console 

Instant transmit 

igh efficiency circuit 

Designed for safety 

Fast band switching 

Real signal impact 

Price .... *795 00 

READY TO OPERATE! 



Hafstrom Technical Products 

4616 Santa Fe, San Diego, Ca. 92109 



FM EQUIPMENT FOR SALE 

We have the following equipment for delivery upon receipts 
of your check or money order: 

Motorola Highband Sensicon A FM receivers. This receiver 
is usually associated with the SOD series of equipment, and 
uses tuneable cavities In the front end. Filaments are wired 
for both & 12 volts* Chassis is housed in a metal shell 
with a quick connector on the rear panel. Price. .... ,$35-00 

Motorola 30 watt high band transmitter. This is a crystal 
controlled FM transmitter. Power output is 30 watts from a 
pair of 2E26*s driven by a 2E26. Also housed in a metal 
shell with connector on rear panel. Matches above receiver. 



Price 



- * . + ■ 



*•*■■■■ 



iitiiiliiiittii i)l JiVU 



Tower supply- This 12 volt power supply provides all op- 
erating volt ages for the above transmitter and receiver. Re- 
ceiver section uses a vibrator* with a dyna motor for I he trans- 



mitter. Price 



*+*#♦♦ 



#■*»*- « ♦**»»- 



.*»*-• 



$15.00 



Mounting rack ran tains wiring to interconnect above trans- 
mitter, receiver and power supply, ait of which plug directly 
into rack. Size, approximately 22* x 22* x ST. Price. .$5.00 

Order all four of the above units, transmitter, receiver, 
power supply and mounting rack for only •*..♦, $65.00 

These are all used units but are in good condition with 
only an occasional lube missing. If you are not satisfied you 
may return the unit in 10 days for refund or replacement of 
the had chassis. 

Bendix AIRT-0. This is a high band 10 watt transmitter, 
receiver and pow?r supply ( all housed In one package. 
Smaller than an SOD this is ideal for trunk mounted mobile. 
Power supply is G4 volts, hut this may be converted to 110 
VAC Tor portable use, or substitute your own 12 volt suPDly. 
I will supply schematic for these units. Price ....... .$30.00 

ONE OP A KIND ITEMS: 

■ 

Motorola dispatcher receiver, for high hand SI 5,00 

Link 1498- 70 to 100 mc. 110 volt input. Easily converted 
to meters as I will supply the original manual Tor this set. 
In rack with line termination unit $45,00 

Bendix MRT-tf; 110 volt input, 30 watt output on high hand. 
This was just removed from a commercial system and is in 
good condition. Price .»...*... *«**. $60.00 



Send check or money order to DUPAGE FM, P.O. Box 
I, Lombard, III. 60148. 

Illinois resident! add 5% sales tax. 



FEBRUARY 1968 



73 





soo 



5 BAND -480 WATT SSB TRANSCEIVER 
FOR MOBILE - PORTABLE - HOME STATION 



■ ■ * » 



ACCESSORIES: 

Full Coverage External VFO. Model 410 

Miniature Phone Band VFO. Model 406B 

Crystal Controlled Mars Oscillator. Model 405X 
Dual VFO Adaptor, Model 22 

12 Volt DC Supply, for mobile operation. 
Matching AC Supply. Model 117XC 



« . 



> a ■ 



...$95 
...$ 75 
...$ 45 

...$25 


...$130 
...$ 95 



Plug-in VOX Unit. Model VX-1 $35 



S 



COTT RADIO SUPPLY, Inc, 

266 ALAMITOS AVENUE 
LONG BEACH, CALIF. 90802 



EQUIPMENT BOUGHT 

ANY SURPLUS MILITARY EQUIPMENT 

Guaranteed highest prices, Payment in 24 hrs. We'll trade o 
give you new ham equipment also, Write or 
Telephone collect, 1 212 ) CY 9 0300 



MILITARY 

4178 PARK AVE. 



ELECTRONICS CORP. 

• NEW YORK* 10457 




HAM TUBES SPECIALS 
BRAND NEW— GUARANTEED 



4CX350A 
4CX250B .. 
4X I BOA .... 
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FG-17 

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TOP 



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4.50 

3.80 



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$$$ PAID FOR TUBES! 
FREE — Ham tube catalog 

120 W. 18th St., N. Y. 10011 

212-242- 



ROTRON 100 CFM FANS 

SENTINALr^-l-Il/ie SQ r 1-I/2D 115 V 60 cy 7.95 

SENTINAL— i-ll/16 SQ x 1-1/2D 230 V 60 cy. .. 9,95 

GOLD SEAL— 4-11/16 SQ x 1-1/2D 115 T SO cy. 6,95 

4 Pole Single Throw Contactor LIS V 60 cy. 

15 amp. Mfg. AH & H, Rowan, etc . . . . 9,95 

All fine condition, working, removed from equipment. Pott- 
paid Continental U.S.A. 

LEEDS RADIO 
57S Warrsn St., N.Y.C., N. Y. 10007 



(W2NSD from page 5) 

to New Hampshire and set about getting 
the subscriptions straightened out from the 
foul-up created by a subscription agency 
that had been handling them for us* 

The shortage of money kept us from hir- 
ing anything but drop-outs, with the re- 
sult that few things were ever done right 
and the letters of complaint generally were 
about equal to the subscriptions. The rich 
get richer and the poor get poorer. When 
these problems did seem to be ebbing I 
immediately bit off another big bite to chew 
, . . Radio Bookshop never made money, 
but it was, I felt, a valuable service, 6-UP 
lost a bundle for us. As did the parts kits 
and ATV Experimenter, But we were pro- 
viding a service, so I kept them going. 

Eventually, as usually happens to fellows 
who are totally immersed in their work, 
I found my wife fed up and divorcing me. 
I reacted about the same as everyone else 
who has been through that misery . , . I 
went into apathy, I could no longer work. 
Paul Franson, who had been our bookkeep- 
er, took over as editor. All of the services 
depended heavily on me and they had to 
go. I stopped trying to sell advertising and 
our ad sales dropped off badly. The great 
bulk of the advertising during this time 
was unsolicited. 

In order to try to break out of my depres- 
sion I made a couple of trips to Europe, my 
safari to Africa and trip around the world. 
Unfortunately the management of the maga- 
zine was left in very weak hands and when 
I got back from my trip I found that the 
magazine had dropped a month behind. My 
safari and trip around the world cost about 
$3500, but in the meanwhile the magazine 
had lost about $25,000 and was in a sick 
condition. 

I set right to work solving the problems 
again. My apathy was solved by the simple 
expedient of finding a fabulous girl and 
getting married again. I solved the late 
magazine problem by moving to a new print- 
er that could get us out on time. This is 
a complicated and expensive procedure. Cir- 
culation problems were still bugging us and 
I decided to make the big changeover to 
a computer for the subscriptions. We're still 
getting a lot of QRM from irate subscribers 
who have been ill-treated by the new com- 
puter, but I hope that we will eventually 
get it tamed and be able to provide the 
best subscription service of alL 



Im working on the advertising again, so 
I hope that we will be pulling ahead a little 
more in the number of ads in 73. The ads, 
as I have mentioned often before, are the 
things that pay for your magazine, so don't 
look your gift horse in the mouth. Be nice 
to our advertisers, patronize them, encourage 
them. 

Kayla has taken over as editor and I 
think we will all be seeing the difference. 
You may find some of her opinions con- 
troversial, but you won't find her writing 
boring and pedantic. Her interest in build- 
ing should result in a lot more coverage 
of construction projects and VHF develop- 
ments. She has some wonderful ideas for 
improving the magazine. 

It was too bad that I had to give up 
the Radio Bookshop. While this activity 
never made us enough money to even think 
about, it did provide a good service to our 
readers and made radio books easily avail- 
able, This took a lot of my time, I had 
to check into all new books published to 
find those that would be of value to hams. 
Then, when I found them, I had to order 
them, make sure they were delivered, pay 
for them, write up ads to run in 73 for 
them, make sure that orders were filled, keep 
the books straight, and keep after publish- 
ers to fill our orders. There was a lot of 
correspondence with customers who couldn't 
understand why we would advertise a book 
and then not deliver for a month or so 
after his order, I would have to explain that 
the publisher had promised delivery, but 
hadn't made good yet. It took an awful lot 
of my time so it had to go when I found 
myself unable to work more than a few 
hours a day. 

The parts kits were another giant head- 
ache. The idea of the project was to make 
Idts of parts available for various 73 con- 
struction articles so that the ham with the 
weak junk box could get in on the fun of 
building without having to order parts from 
a dozen different sources. We thought that 
since few distributors were trying to sell 
parts that there would be little trouble from 
them, but we reckoned without the help of 
CQ, They got right to work and wrote let- 
ters to all the distributors screaming that 
we were trying to put them all out of busi- 
ness, A few of the more hysterical dis- 
tributors believed CQ, but most realized 
that our project would hurt no one and, 
to the contrary, might just encourage more 



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543 W. 184th St., Gardena, Calif. 90241 



TH ANNIVERSARY 

SPECIALS FROM 




GIANT SIZE 

SPINNER TUNING KNOBIIIII 

3'* knob for '/V shaft complete with 
handle bushing for fast and careful 
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buy than make, and faster too, 

POSTPAID IN USA $2.00 

BENDIX MRT-? TRANSCEIVERS 

RECEIVER — Double conversion 13 
tube superheat. Better than 1 micro- 
volt sensitivity. Complete with crys* 
tab set at 138 mcs. Easy to adjust 
to Satellite frequencies. TRANS- 
MITTER— over I watt output to 146 
mcs. FM. Complete with vibrator 
supply (less «v Vib.) with all tubes 
and crystals. Original Selling price 
In commercial form $2?5.00 

Our 20th Anniversary Special $39.95 

IP7JC Kit; for above MRT-7, con- 
tains power supply, speaker, 6, 12, 
24, 32 dc and 117 volts AC which 
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Limited quant. Used, good cond. 

$24.50 
Both units, MRT-9, IP7IC, ordered 
at one time. SPECIAL!! $59.95 



VARIABLE INPUT FILTER 

Discriminates against spurious sig- 
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signals, Originally used in exciter of 
Navy transmitter. Brand new boxed 
in 4" v 3" x 3" aluminum container. 
Contains band switch, dual gang 
variable, iron core coils [&}, re- 
sistors, condensers, tuning range 
2-1.5 mcs. Makes good foundation 
unit for VFO, GD, etc. See previous 
CQ articles and comments by Wil 
Scherer and Gordon White. 

POSTPAID IN USA $3.95 

LIMITED QUANTITY ITEMS 

CV-473 FACSIMILE TRANSMITTING 
CONVERTERS Mfd by Crosby Elec- 
tronics. Outgoing frag, 1500 to 
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frequency. Can be used for TT with 
some modifications. Operates on 
117 volts 60 eye. 600 ohm input 
and output. 

BRAND NEW, A STEAL AT $4930 
TP-14 TELEPHONE REPEATERS. 

Loaded with 600 ohm hybrid trans- 
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used. $14.95 



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ALVARADIO INDUSTRIES 

3101 Pico Blvd., Santa Monica, Calif. 90405 
phones: 213-870-0216 Ask for Harry W6ATC 



hams to get in on the fun of building and 
that everyone might be the winner in the 
long run- 

The parts kits took a tremendous amount 
of mv time. I had to make sure that all the 
parts' were on hand and put the parts into 
the kits for each one. I had to get boxes, 
write and print instructions, keep the rec- 
ords, pay the parts bills, etc, Such aggrava- 
tion. It was nice to stop all that. 

One more year of red ink fust might 
sink us, so tVe been encouraging a cut 
back in our staff. Paul went down with 
Davco. Jack has retired. And Jim is busy 
trying to start his own ham magazine. I 
gather that he has been working with a 
wealthy New Hampshire ham for almost a 
year now on the plans. With our reduced 
staff of four paid employees I think we 
will be able to get 73 back into the black 
and even be able to keep our subscription 
rates as their present level for some time 
to come, I notice that CQ is raising their 
rates. 

I'm back on my sixteen hour work days 
again. I don't know how long Lin will put 
up with it, so I hope that we can get 
enough advertising and subscriptions so I 



can occasionally take a day off for some 
skiing or a dinner out with her. I had hoped 
to be able to take her to Europe, paying 
for the trip by running a tour next spring, 
but I can see now that there really is no 
way that I can get away from the magazine 
for the three weeks required while I am 
handling the advertising and publishing. It 
is very disappointing to have to give up 
our plans for the trip, but it will take longer 
than spring before we are back on solid 
financial ground. 

Perhaps the apathy over my own prob- 
lems explains the lack of aggressiveness for 
the last couple of years in 73, It must be 
that because things certainly have not been 
going well in our hobby. Incentive licensing 
has done a lot to change ham radio. CB 
has had an effect too. There are probably a 
lot of other factors which have acted to re- 
duce interest in ham radio and to cut down 
the sales of equipment and parts to hams. 
I don t think there is much purpose in 
bearding the villain. It seems to me that 
we should now get started at meeting our 
world as it is and stop grumbling about 
how it is or who made it that way. 

The bulk of us are having to face the 



76 



73 MAGAZINE 



reality that if we are going to continue to 
enjoy all of the ham frequencies we are 
going to have to go down to the FCC and 
pass a new and tougher examination. Dur- 
ing the next year I would like to publish 
a lot of good basic theory articles which, 
taken together, will make it possible for 
all of us to pass these new tests. This is 
a good opportunity for those of you who 
have done some teaching and who would 
like to do some writing to put together 
some articles for us. I want to see simple 
and complete explanations which will give 
us the understanding to handle the new 
exams. How about it? 

Another thing I'd like to see is some 
more humorous articles. There is no shortage 
of foibles in ham radio to be kidded. If 
you enjoy writing a good humor story you 
might turn your talent to any of the major 
ham interests . . . traffic handling . . . 
mountain topping . . . VHF pioneers in 
empty bands ... the lonliness of the moon- 
bounce operator . . . DX contests . . . 
DXpeditions, unless Miller has killed them 
for everyone ... I see that Miller has 
found a publisher for his DX book. I looked 
over his outline, decided it was a hodge- 
podge, and wrote my own book which, with 
luck, will be out by the time this is printed. 
Articles ... the 75M DX crowd ... the 
160M DX addicts ... the poor souls who 
are stuck high up on the ARRL Honor Roll 
. . . the mobile DXer ... the CW mo- 
bileer . . . etc. All you have to do is listen 
in on any band for a few hours and the 
articles will write themselves. We'll print 

them if I laugh. 

If you don't mind too much well let the 
other ham magazines stick to being serious. 
Our hobby may be a service in the eyes 
of the ARRL, but to me and a lot of others 
it is enjoyable ... it is fun. I suspect that 
as soon as amateur radio stops being fun 
it is going to fold up, so let's stress the 
fun side of our hobby. It is fun to build 
. . . it is fun to operate ... it is fun to 
do unusual things. Let's see what we can 
do to make as much of amateur radio fun 
as we can. I always remember a fellow 
TV director who explained that he used to 
go in for boxing, then one day he found 
himself being beaten to a pulp in the ring. 
He suddenly discovered that he wasn't hav- 
ing any fun and that was the last time he 
ever fought. 



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5BDT 



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TH-2 Beam 



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H G J ELECTRONICS 

E. 6904 Sprague Ave* 
Spokane, Wash. 99206 



GO VHF 

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way. Send for descriptive Technical 
Bulletins describing our complete 
line of TRANSISTOR RECEIVING 
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DENVER, COLORADO 80222 



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The following list represents a 
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ins 



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279 
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99 



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345 



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10 

65 



275 

50 



325 
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185-191 W\ Main St. 

Amsterdam. N. Y. 12010 
518-842-8350 



FEBRUARY 1968 



77 



&£SP&* 



VALUABLE books from E.&E 



C& SIHCII SIDEBAND: 

^^ THEORY AND PRACTICE 

by Harry D.Hooton, W6TYH* The 

one-source guide to ssb. 
Covers the origin and 
principles of ssb, deriva- 
tion of ssb signals, car- 
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balanced mixers and converters, low-power 
ssb transmitters, linear r-f amplifiers, ssb 
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RADIOTELEPHONE LICENSE MANUAL 

Helps you prepare for all commer- 
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You can make ham radio fun for others 
by keeping in good spirits on the air and 
refusing to let illegitimate sons wear you 
down. You can make publishing 73 fun for 
me by putting up with our bumbling here 
and encouraging other amateurs to read 
the magazine. 1*11 do everything I can for 
you and Til try to let you know what is 
actually going on in our hobby, good and 

had. 



Merchant Marine 

There is a great shortage of shipboard ops 
these days, I thought this might be of interest 
to some of you younger fellows who are look- 
ing for a way to make ham radio pay off for 
you. You could do worse than check into the 
requirements and the draft avoiding possi- 
bilities. The money is rather nice too, run- 
ning about $600 to $800 a month and most 
of that in the clear. 



Burma 

Editorially I am still wandering around the 
back reaches of Asia. In truth 1 am sitting 
comfortably back in New Hampshire waiting 
for the heavy snows to bring the skiing sea- 
son to northern New England. The whole 
trip, including the safari hunt m Africa of 
two weeks, only lasted about twelve weeks. 

I might have skipped Burma if they hadn't 
tried so hard to keep me from coming. I'm 
that way, as you probably know if youVe 
been reading 73 for any length of time. By 
tenacity and amazing luck I managed to find 
myself deplaning last September at Rangoon 
airport late one afternoon. My visa for Burma 
was by far the most difficult to get; requir- 
ing days of waiting on the Burma Mission to 
the ILN. in New York, I had no idea what 
lay ahead since, as far as I could find out, 
nothing had been written in any of the popu- 
lar or travel magazines or books about Burma 
since the army coup five years ago. The 
amateurs had been put off the air at the time, 
so I had no personal contacts to follow up 
as I had in most other countries. 

There were just three of us on the entire 
plane flying from Calcutta to Rangoon and 
the other two were obviously Burmese gov- 
ernment officials. They were met by cars at 
the airport, leaving me to run the gauntlet 
of customs and immigration alone. 

The first step was to fill out a currency 
declaration listing every bit of money that I 



78 



73 MAGAZINE 



had with me. They check this when you leave 
the country to make sure that you haven*t 
exchanged any foreign currency at other than 
the official exchanges. You have to have a 
receipt for every dollar exchanged. The rea- 
son for this is that they have a very serious 
inflation there and the world exchange rate 
is about 15 kyats to the dollar, while the 
official rate is under 5 to the dollar. This 
means, practically speaking, that everything 
costs vou about three times normal. 

Then, while the customs men were exam- 
ining my baggage, I signed into the log book 
for entering the country. I looked back 
through a few pages to see if any other 
Americans had visited recently, but could 
only find entries for U.8.S.R. and the People's 
Republic of China for the last few weeks. 
Apparently I was the only American to visit 
Burma in quite a long time. 

A small bus drove me from the airport 
about twenty miles to downtown Rangoon 
and the Strand Hotel. My room was $12 
a night, but it was a large room with air 
conditioning and a bath. This was over three 
times the price of the same accommodation 
in India, It was about dark when we got to 
town so I didn't get a chance to see very 
much. 

My first move was to try to locate a local 
amateur that I'd heard about from the ama- 
teurs in India, but he wasn't listed in the 
phone book. I asked the hotel manager about 
Miller's visit there the year previously. He 
said that he had no record of a Miller visit- 
ing and was sure that no radio amateurs 
had either visited or been permitted to op- 
erate from his hotel I didn't know what to 
make of this for Don had claimed to have 
been there. 

After dinner I decided to make a major 
try to locate the local ham* I asked the bell- 
hop to get a taxi for me and, after quite a 
wait, he arrived with a fellow on a bicycle 
with a small side seat fastened on. I gave 
him the address and he said he knew right 
where it was. Well, we drove around the 
back streets of Rangoon for about an hour, 
with him asking people where the street was 
we were looking for. Finally we found it; 
an old shabby building, all black. It looked 
deserted. The whole neighborhood looked 
deserted. I knocked. 

There was a long silence, then the door 
opened just a crack. I quickly shoved in a 
QSL card. The door was flung wide open; 
"Come on in, I'll get my father, sit down/' The 



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SEE YOUR DISTRIBUTOR OR WRITE FOR CATALOG 



Tush 




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MANCHESTER, N.H. 03103 



FEBRUARY 1968 



79 



73 SUBSCRIPTION BLANK 



$5 one year 



_ $9 two years 



$12 three years 

$50 LIFE 

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$3 DX Handbook 
$2 VHF Antenna Handbook 
$1.50 Index to Surplus 
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whole family gathered around and explained 
what had happened to Burma and amateur 
radio in their country , 

Rangoon used to be a paradise. It had a 
large middle class population and was one of 
the fastest growing and most advanced cities 
in southeast Asia. The people owned and ran 
the businesses . . . they had beautiful homes 
and nice summer places, clubs, restaurants. 
Then, about five years, ago, the army over- 
threw the government and everything 
changed. First they took over all of the 
banks and confiscated the bank accounts. 
Next they issued new currency to be sure 
that no one had any savings in cash put 
aside for the future. The largest denomina- 
tion of the new currency was about equal to 
a dollar (five kyats). This made it so that 
even if someone was able to gather a good 
deal of money it would be so bulky that he 
would have a very difficult time carrying it 
around. 

The new government then proceeded to 
take over every business in the country, large 
and small, excepting only small family run 
restaurants- They gave no compensation for 
this takeover. They put the pressure on all 
foreigners living in the country to get out as 



soon as possible, cutting off all possible in- 
come, food supplies, clothes, and even visit- 
ing friends. They harassed them and most 
of them left, including people who had de- 
voted their life to working and living in 
Burma. Most of the businesses appropriated 
by the government simply closed. All ama- 
teur radio priviledges were suspended. 

Schools, hospitals and all other such or- 
ganizations were taken over and the bulk of 
the staffs dismissed or changed. Clubs and 
restaurants were taken and closed, Every 
business that is running today, large or small, 
is owned and run by the government. All 
automobiles were confiscated. Machinery of 
any value was removed from all companies 
that closed down. 

This has been very hard on the people. 
They were used to a relatively high stand- 
ard of living, now, with everything at a 
virtual standstill, the smallest item is rationed 
and government red tape stands between you 
and any purchase. Prices are astronomical 
Just about all trading is done via small suit- 
cases in the rapidly moving black markets. 
For instance soap is rationed one bar to a 
family per month, , t one suit of clothes per 
year. If someone is fortunate enough to have 



80 



73 MAGAZINE 



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Complete as shown total length 102 ft. with 96 ft, of 72 ohm 
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just tune to desrred band. Excellent for ALL world-wide 
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AND ALL CLASS AMATEURS! Eliminates separate an- 
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Fussy Neighborhoods! EASY INSTALLATION! Thousands 
of users, 

75-40-20-15-10 meter bands. Complete ..,$19.95 

40-20-15- 10 meter. 54 ft. (best for gwFsh Complete ..$18.95 
SEND ONLY $3.00 (cash, eh., mo) and pay postman balance 
COD plus postage on arrival or send full price for postpaid 
delivery, Free information. 
MIDWAY ANTENNA • Dent. A-2 * Kearney, Nebr. 68847 



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Send for technical brochure 
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COMMUNICATION RECEIVER 

RCAF GR-10 COMMUNICA- 
TION RECEIVER— IIS Volt 25- 
60 eye, & Bands; 195 to 410 KC 
& 1400 to 31000 KC, electric 
band spread, var. selectivity, 
ad(» crystal filters, noise limit- 
er, AVC, carrier strength me- 
ter, crystal control on any one 
freq. to 6.0 MC„ temp. & voltage reg. of oscillator, 
sensitively better than 5 Mie. V. 2:1 sig. to noise ratio. 
Max. undistorted output 3 watts. With Tubes: 3/6SK7, 
I/4K8, l/6SJ7 T I/6H4, I/6SQ7, I/6F6G, I/5Y3G, & l/VR- 
105. Beat freq. osc, control & prov. for speaker 4 head- 
set. She: W/ 2 x 20 x IH/ 2 "; WC: 85 lbs, (Cabinet de- 
sign may vary,} 

Prices: Used — Not Checked ...$39,95 

Used — Checked ........ _$99.K 

TRANSMITTER— RECEIVER W/S 
CDN No. 29 "B" SET 

Appro*. 230 to 240 MC. with 12/24 
VDC Power Supply self contained* and 
Tubes: 4/6 AGS, 2/&AK6, 2/6C4, & 3/6J6. 
Two preset channels in the freq. 
range. (Ideal set for local netting on 
I'A meters.) Size: 4>/ 2 x 8 x II"; Wt.: 
18 lbs. Price: Used $18-95 




NAVY TCS RECEIVER AM— 1,5 to 12 MC in 2 bands 
For details see our ad in the January, J G8 issue. Used: $44.95 

NAVY TCS TRANSMITTER AM— 1.5 to 12 MC in 3 
bands. See full description In our Jan., *m Issue ad. 
Used , $34.50 

Both above Items — Checked for Operation: $10.00 additional. 
Prices F.O.B. Lima, O. — 25% Deposit on COD'a. 

BIG FREE CATALOG— New edition just off the 
press 1 Send for your FREE copy today. Address Dept, 73. 

FAIR RADIO SALES 

DEPT. 73 — P. O. Box 1105 — LIMA, OHIO 45802 



WANTED: July 1962, July and August 1966 issues 
of 73 Magazine. WA1GHW, Bt. 1, Box 571, Terry 

Rd., Gales Ferry, Conn. 06335, 

MECHANICAL ELECTRONIC DEVICES CATA- 
LOG 10^ , . . Teletype Model 14 reperforator with 
automatic tape take up rewinder 115VAC60cy. 
Both units new, unused $69.95 , , . ARR27 Re- 
ceiver 29 tubes 465-510 MHz w/60 MHz if new, 
unused $35 . . . 1/16 laminated copper clad 2 oz, 
2 sides, for printed circuits %%%&*& $1 „ . . 3/$2, 
Transistor boards bonzana §5.95 . , . Wide band 
balanced modulator $4.95 ... 30 MHz IF Assem^ 
bly $5.95 . , t Transmitter TDG w/Modulator 
easily converted to 2 meters $49.95 . . . Low pass 
filter 0-32 MHz 52 ohm $9.95 . , , 5KV/2KV/1KV 
at 750 ma/2Q0ma/250ma Power supply write for 
details. Fertik's, 5249 "D*\ Fhila., Pa. 19120. 



TOROIDS, uncased 44 or 88 mrl, also individually 
epoxy encased 88 raH for standards, any 5 $1.50, 
255A relay $2.10, 18B socket 70c 1 all PP USA. 
E. W. Evans K40EN, 220 Mimosa Lane, Paducah, 
Ky. 42001. 

FOR SALE. Ranger $60., SX110 $89, ARC-3, two 
meter Xmtr $20, wanted FM equipment. WA5FFK 
804 So. 6th, Blaekwell, Okla. 74631, 

GONSET 2 METER SIDEWINDER: CW-AM-SSB, 

complete with AC &: DC power supplies. Recently 
factory aligned. $230. K7DGV John Stiles, Sweet- 
grass, Mont- 59484. 

— 

WRL's used gear has trial-guarantee-terms, 
NC270 — $139.95; HQ170AC — $239.95; HQ110AC — 
$169.95; 75S-1— $299.95; 75A1— $169.95; SXIOO— $134.95; 
HAIO — $189.95; HT32 — $249.95; GSB100 — $179.95; 
Ranger 2— $169.95; G76 — $99.95; 650 & VFO — $89.95; 
Thor VI Sc AC/PS— $169.95, Hundreds more. Free 
"Blue-Book' 1 list. WRL, Box 919, Council Bluffs, 
Iowa 51501. 

SELLING: HQ-145C. $150; Valiant, $140; BC-221 
frequency meter, S50; C.E.-20A plus VFO, $100; 
HT-37, $200; Wanted: Drake DC-3. K9FWF/9, 114 
North Orchard, Madison, Wisconsin. 

FCC 1ST CLASS RADIOTELEPHONE LICENSE 
COURSE. Current, used, complete including radar 
ind. 70 lessons $60. W6UFZ, 508 Grape St,, 
El Cajon, Calif. 92021. 

BRAND NEW Factory fresh test equipment and 
other electronic items at unbelievable prices. 
Send for complete catalog. DRC, 215-28 Spencer 
Avenue, Queens Village, N.Y. 11427, 

TRADE Teletype equipment, Vidieons or what 
have you for G.E, Progress Line FM units or 
parts. All inquiries answered, W40CQ, 1037 
Creamer Rd.. Norfolk, Va. 23503 Ph. 703-587-6287 
Collect, 

ROCHESTER, N*Y. headquarters again for the big 
Western New York Hamfest and VHF Conference 

Saturday, May 11. 

H A LLIC RAFTERS SR-42A new, never used, orig- 
inal carton, matching HA-26 VFO, Shure 404c 
Mike— $200.00, Jeff Ross 125-12 Cronston Avenue, 
Rockaway Park, N.Y. 11694, 



GALAXY V, AC SUPPLY in mint condition used 
very little $290. WA0JYC, 1208 Gail Ave., Millard, 
Nebr. 68137. 

NATIONAL NCX-3 and NCX-A perfect condition. 

Sacrifice for college $225. Randy Brook WA2FPE, 

534 W. 114th St., N.Y.C. 10025 (212-662-0232). 



™ 




jr Price — $2 per 25 words for non-commercial ads; $10 
per 25 words for business ventures. No display ads 
or agency discount. Include your check with order. 

jr Type copy. Phrase and punctuate exactly as you wish 
it to appear. No alt-capital ads. 

* We will be the judge of suitability of ads. Our re- 
sponsibility for errors extends only to printing a cor- 
rect ad in a later issue. 

it For $1 extra we can maintain a reply box for you. 

* We cannot check Into each advertiser, so Caveat 
Emptor i • - 



;c Eico 753 Transceiver, $140. Eico 753 Kit, 
unopened box $140. HW-12/HP-23/mic, $140. AH 
excellent and transceivers on the air. First check 
takes either -, « . Specify. K9VWQ, 1205 Tangle- 
wood Rd., Manitowoc, Wisconsin. 

^^_ ^ 

SWAN 350 with 117Xc Power Supply $375. Heath- 
kit Seneca Six-Two transmitter with external 
VFO $125. Stephens, W2NTZ, 3048 Wilson Ave., 
Bronx, New York 10469. 



SUPER SALE, Micro Switch 10 A 250V— 99tf, 5894^- 
$9, 68S3 (6146)— $2, 2C39— $3, 416B— $5, 4X150— $5, 
4-400— $19, 833— $19, 3CX10.000— $39, 4-125— $14, 
6155— $14, 7378— $19 p 5867— $19, 3X3000^519, 3WP1— 
$9, 6166— $49, 7038— $29, Eimac SK300 Socket— $19, 
SK712 Socket— $9, Vac. Var. Condensers— $19, 5 Ft 
dish— $49, Dual Xtal Ovens — $1, 50-0-50/*a Meter— 
$3, Incrm, Osc, Units, lOXtals 10 to 11 Mc t , Toroid 
Step Relay, Switch, Etc. Beautys, $3* Sola Regu- 
lat, Xformers 120PRI, 350 Sec— $4, 5% resistors, 
any value 5tf, Daven Pads — $4, WA8GFR, 1423 West 
52nd., Cleveland, Ohio 44102, 

DAYTON HAMVENTION April 27, 1968— Wampler 
Arena Center, Dayton, Ohio, sponsored by Day- 
ton Amateur Radio Association, QSO in person 
at the nations foremost radio event of the year. 
Technical sessions, exhibits, hidden transmitter 
hunt. Bring the XYL for an outstanding Ladies 
Program. Join the satisfied participants who re- 
turn year after year. Watch the Ham ads for in- 
formation or write Dayton Hamvention, Box 44, 
Dayton, Ohio 45401. 



WANTED — Will pay good price for clean unmodi- 
fied SX-115 Receiver, Albert Horn WA2WMQ. 1135 
Glenwood Rd M Toms River, N.J. 08753, Phone 
201-341-9286. 



TRADE HQ-110 for Johnson KW Matehbox, table 
top linear, or SR610 Monitor Scope, Tom Thur- 
man Jr., Rt. 5, Sparta, Tenn. 



NATIONAL NC303, 6 meter converter, XCU-27 
calibrator, mint condition, $275. Utica 650 Six 
meter transceiver, VFO, mike, $130. Richard 
Ravich, 10 Coolidge Road, Marblehead, Mass. 
01945. 



WANTED broadband coil also crystal for lOOv for 
160 meters. WA6WXJ, Charles Harper, 131 Hill- 
crest Drive, Daly City, California 94014, 

3000 V @ 3 M F brand new GE Pyronal oil capaci- 
tors $3 each. Can mail. 3-lbs each shipping wt., 
FOB P. Wandelt, RD #1, Unadilla, New York 
13849. 

COLLINS 32V3 Very good condition $150,00, man- 
ual included, extra 4D32 final $10.00, WB2GPR 
Bill Donson, 5 Division St., Binghamton, New 
York 13905. 



REGULATED POWER SUPPLY. 225 v @ 550 ma- 

115v @ 100 ma. 4/6,3v @ 12a. Fully metered. 19 
inch rack panel. 150 lb. $39.95, Write, Electronics 
Surplus Co M P.O. Box 1225, Boston, Mass. 02104. 

HIGH VOLTAGE RADIO GENERATOR. Type 

(1) 3000 Volt. Type (2) 250/1500 Volts. Unused. 
Ship anywhere, $75.00. FOB Boston. Write Elec- 
tronics Surplus Co. P P.O. Box 1225, Boston, Mass. 
02104, 

H A LLIC RAFTERS SX-101A, speaker, headphones, 
spare tubes, manual. Perfect condition, Profes- 
sionally maintained. Wollensak T-1500 Electronic 
control recorder. Bob Yarmus, K2RGZ t 5900 Ar- 
lington Ave., Riverdale, N.Y. 10471. 212-884-6336, 

WANTED — Gonset 2 meter linear, II or III, must 
be mint— cash. Sale or Trader NC-303 Cal. spk & 
manual mint— $275. SP-600 RX in cabinet $300. 
J, Gysan W1VYR, 53 Lothrop St., Beverly, Mass. 
01915. 

SWAN 350 with VOX and Calibrator, Mike. Ex- 
cellent condition, no modifications, like new $300. 
K1E J W— Roland, Lowell, Mass, 458-1892. 

AUCTIONFEST— B.A.R.C. — February 17th. Bar- 
gains unlimited. Location — Chaminade High 
School* 500 North 51st Ave., Hollywood, Florida* 
Doors open 8:00 AM, auction starts 9:00 AM. Free 
Coffee. 

THE NORTH JERSEY DX ASSOCIATION is 

sponsoring its annual DX Round-Up on Saturday, 
March 23, 1968 + This is the Saturday following the 
IEEE Convention in New York and it is expected 
that many out-of-towners will find it convenient 
to attend. Site of the Round -Up is the Holiday 
Inn, Wayne, N.J. at the intersection of Route 46 
and Route 23, just 30 minutes west of the George 
Washington Bridge- The afternoon program starts 
at 2 P.M. and banquet at 7 P.M. Further details 
available from W2PXB. 

COLLINS SSB STATION: KWS-1 Ser 1246, 75A4 
Ser 4950, SC101 Station Control, Bandpass filter 
and table top. Will deliver to 400 miles., lot 
$900,00. Also Swan 350 t 117X power supply, 14X 
DC module and mobile cables. Little used, $400.00 
FOB W4CNC Vernon A. Sanders, 3105 Dyas Dr. 
NW, Huntsville, Ala. 35810. 

100 EPOXY DIODES 1,2 amps, 1000PIV $20.00. 800 

PIV $18.00. 600 PIV $14.00. See page 96 Dec 73. 
Check with order. Postage Paid. Pete Fragale 
WSAEN, Box 585, Clarksburg, W, Va. 26301, 

COLLINS 62S-1 like new $600.00 or best offer. 
Will trade on Collins 30S-1 KW Amp. W4LZP, 327 
Chamberlain St., Nashville, Tenn. 37209. 

LATE MODEL SWAN 350 w/AC p/s $300.00, Will 
accept Delta or equal wood lathe, jointer or 
shaper in trade. John E. Bagwell, Somerville, 
Tennessee 38068. 



FEBRUARY 1968 



91 



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SILICON RECTIFIERS \ 

FIV Sob piV Sol** 



SO 

100 
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400 



□ 

a 

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(Replaces) Sale 

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□ 1N1262 6AU4GTA) ..2.39 
P1N2637 866A) 9.99 

□ 3DG4) 2.39 




400 

NPN 
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for$| 

2N706 n 

Watti) y cti Hu | ma 





.5 30 I to -300 150 



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200 □ 39c 1000 C 791 

400 C 45, 



NOW 



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PMAMP 4 

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top* Amplifier, radio, TV 

it Vol u me, Tone, Controls s* 



n 




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CBO 100 
(AMP) 15 $ 



2 



25 



AMP TOP HAT AND EPOXIES 
SILICON RECTIFIERS 

2000 

PIV 

1.5A 



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50 U 5« 
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50 
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6 8 16 25 

AMPS AMPS AMPS AMPS 

— □ -42 Q -61 □ J* 

.85 D -59 D -89 D .95 
135 □ ,89 1,15 

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ALL ITEMS GUARANTEED AS ADVERTISED 
OR YOUR MONEY BACK 




H 



Waterproof Connections 

Just a hint for anyone who needs a per- 
manent type of seal for wire splices and 
connections which are to be exposed to the 
weather. 

A liquid plastic called "Plasti-Goop" is 
on the market for kids toys. It is distributed 
by Matte] for "Thing Makers" and other 
toys. The plastic liquid can be applied di- 
rectly to the connection, or whatever one 
wishes to be sealed, then it must be heated 
to about 300 degrees for a few minutes to 
cure it The Plasti-Goop is not flamable, 
and may be heated with a propane torch 
or over a gas burner for curing. Plastic 
coated wires, such as twin-lead, must be 
treated with care not to melt the insulation. 

Two or three layers are needed to make 
a good seal and insulator, This has been 
used to good success here, especially on 
rubber covered wires. If you have a cir- 
cuit which must be exposed to the weather 
and need not be disassembled or adjusted, 
the entire circuit can be filled and baked 
in an oven to cure at about 200 degrees. 
The plugs on the end of extension cords 
are a good place for this. It makes a neat, 
waterproof, and electrically sound connec- 
tion. . , , James L. Townsend K9BXG 



"ARCTURUS" SALE 



• Tube Bar gains, to name just a few: 



New Books from Sams 

ABC's of Radio and TV Broadcasting, by 
Far] J. Waters, tells what is involved when 
you turn on a radio or TV set in terms 
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Mathmatics has been avoided and the ma- 
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List Price $2.25. 

FET Circuits, by Rufus P. Turner, starts 
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Any unlisted receiving tube. 75% discount off current List prices. 

• Tube Cartons: 6AU6 etc, size. $1.75 per 100. 6SN7 etc, siie, 
$2.10 per 100. 5U3GB s.ze, $2.50 per LOO. SLUG size, .03e each, 

• Obsolete Tubes; SUX200. SI -69; =80. $1.20; ^I0Y» 69c, 

• 7 inch 90 degree TV bench test Picture Tube with adapter. 
No ion trap needed. Cat. -7BP7, $6-99. 

• Silicon Rectifier octal-based long-life replacement for 5U4. 
5Y3, 5AS4, 5AW4 P 5T4, 5V4, 524. With diagram. Cat. sReet 
I. 99c each. 

• 0Z4 Silicon Rectifier replacement, octal based. Cat. =Rect 2. 
99c each. 

• 10 Flange] ess Rectifiers, I amp. 400 to 1000 p.i.v. Cat. 
^RSLO, S2.96. 

• 10 Silicon Rectifiers, 750 MA, 50 to 300 p.i.v. Cat. -330F, 
99c each. 

• Condensers; 50-30 MFD at 150 v., 39c each. 3 for SI. 00. 
Cat. -80; 850-400-100-15 MFD at (6-16-4-115 v., 3 for 79c. 
Cat. -82Y, 

■ 2 Silicon Controlled Rectifiers, I amp, general purpose units 
with instructions. Cat. "SCR I, $1.00, 

• 5 Transistor Circuit Boards containing up to 6 transistors, 
plus diodes, resistors, capacitors, etc. Cat. -TBI0, 99c. 

• Needles: values such as -AS22 Saphire, 39c; Diamond. 99c 

• Color Yokes, 70 Degree for ail round color CRT's. Cat. 
= XRC70, $12.95, 90 degree for alt rectangular 19 to 25 Inch 
color CRT'S. Cat, -XRC90, $12.95. 

• Transistorized U,H.F. Tuners used in 1965 to 1967 TV sets 
made by Admiral. RCA, Motorola, etc. Removable gearing may 
vary from one make to another. Need only 12 volts d.c. to function. 
No filament voltaut needed. Easy replacement units. Cat 
-U.H.F, 567, $4.95. 

• General Electric U.H.F, miniature Transistorized Tuner. G.E. 
Part ZET85X-33. Cat. #GE85, $4.95, 

• F.M. Tuner, Hi-Fi amplifier tuning unit complete with dia- 
gram, 2 tubes. Sam's Photofaets -620 lists 2 applications. Cat, 
-FM20, $3.98. 

• Flyback Transformer in original carton. Made by Merit or 
Todd. Most with schematic drawing of unit. Please do not re- 
quest specific type. Cat. -506, 99c each. 

• Flyback Transformer Kits. 2 flybacks per kit. #502E, Emer- 
son: -502Y, Silvertone: *5D2W. Westinghouse; ^507, Phi ho; 
#502 t RCA. Any kit $2.99. 

» Kit of 30 tested Germanium Diodes. Cat, #100, 99e. 

• Kit of 10 NPN Transsistors. Cat #371, 99c JO PNP Tran- 
sistors. Cat. #370, 99c. Alt tested. 

flnul for our Free Tata log Hating thousands of similar best buys 
in tubes, part*, kit*, transistors, rectifiers, etc. Order under 
$5,00. add flOc handling charge. Include \% of dollar value of 
order for pontage. 

ARCTURUS ELECTRONICS CORP. 

502-22nd St., Union City, M.J. (37087 Dept. M73 

Phone: 201-UN 4-5568 



GO COMMERCIAL - - - 

That's right. Set your FCC commercial oper- 
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your "hobby** field — radio and electronics. We 
prepare you by correspondence, under our ''get 
your license or your money back*' warranty. Set 
full details in our free "FCC License Course 
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Grantham School of Electronics, Dept. R. 
1505 N. Western Ave., Hollywood, Calif. 90027 



SURPLUS ELECTRONICS 

Ports & Equipment — New & Used Horn Gear, 
Send 10c for our latest flyer, and we'll put 
you on our mailing list. 

JEFF-TRONICS 

4252 Pearl Rd. Cleveland, Ohio 44109 



FEBRUARY 1968 



89 



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NEW! Horn License Frames 

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ground 




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P.O. Box 3446 
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LARGEST SELECTION In United States 
AT LOWEST PRICES— 48 hr. delivery 

Thousands of frequencies in stock. 

Types Include HCe/U. HCH/U. 
FT. 24 1, FT-243, FT- 171, etc. 

SEND I Of for catalog with oscillator 

circuits. Refunded on first order. 

2400B Cryrtel Dr.. Ft Myers. Fie. eSWt 




CRYSTALS 



J 



Dear 73, 

The following equipment was stolen from me during 
ThanksgivinK week: HQ120 and lar^e speaker. Num- 
bers and dates marked beside each tube socket: HQ140 
and defective speaker (both gray) most knobs have 
white indicator marks added ; KLH-S FM radio and 
matching speaker in wood cases ; Triplett #630 VOM ; 
RDO Shack — small tube tester; Zenith "Lonif Distance 
66" translator portable radio (black) ; and Bausch and 
Lomb 20X Black target spotting scope. Notify Police 
Detective Bureau, Weymouth, Mass. 

Art Bates WIRY 
Hingham, Massachusetts 



Cheap and Rugged Portable 
Speaker Enclosure 

Having a spare speaker which we wanted 
to use for an extension from the shack when 
monitoring a net frequency and for the car 
when we went mobile, we found the perfect 
solution in the plastic foam boxes in which 
electronic equipment is shipped. 

It takes only a little work with a knife 
to hollow out the inside to fit the speaker, 
plus an icepick to punch holes for mounting 
bolts. The porous nature of the plastic foam 
makes punching holes for the sound un- 
necessary, however, the material was so easy 
to work we punched the extra holes any- 
wav. 

The cushioning effect of the foam pre- 
vents damage to the speaker when moving 
it from place to place. 

. . . Ross A. Sheldon K4HKD 













G 



w 



Portable speaker case made from styrofoam box. 



RADIO TELETYPE EQUIPMENT 

TELETYPE MODELS 29 KSR, 28 ASR, 28 KSR, 
28 LPR, 28 LARP, 28 LXD, 28 LBXD1, 14* 15 p 19, 
Page printers, Perforators, Reperforators, Trans- 
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51J-3, R-388, 51J-4, R-390A- Hammerlund SP- 
6Q0JX. Frequency Shift Converters. 

ALLTRONICS-HQWARD CO. 

Box 19, Boston, Moss 02101 Tel: 617-742-0048 



88 



73 MAGAZINE 



, What I am trying to bring out is that we 
should clean our own house first, I'm sure that every- 
time you tune across an active ham band you will 
be able to find signals that are splattering across 6 to 
8 kHz of the spectrum, I'd appreciate being notified 
if mine is doing that. 

With the present conditions, and incentive licensing 
becoming a reality quite likely we will find that 
more, rather than less, used equipment is being made 
available to the CR'ers or whoever might desire to 
buy it- 
Max Casselman WApGSY 
Conway Springs, Kansas 

Dear 73, 

Hail to Ron Zurawski ! Finally, someone comes out 
with an intelligent view of SSB, as well as something 
to do about the CB mess. 

His article contains some very good suggestions for 
what to do with the 11-meter circus which is now in 
full swing. The most important idea is to increase 
the FCC monitoring force. This is urgently needed. 
I know many CB'ers who work with well over 100 
watts, and I even know those who have worked into 
the midwest and west coast with only five watts. The 
thing is, as long as there are CB'ers, there will be 
violators. Still, if the laws were harsher and strictly 
enforced, there would be less CB'ers, and much less 
violation. 

So, bravo to WA8FVD. 

Mark L, Cohen WN3HST 
Philadelphia, Pennsylvania 

Dear 73, 

I'm writing in the hope that this letter may be 
published. My message is extremely simple. Lay off 
W1AW when code practice is being sent! I'm not in- 
terested in the views as regards ARRL, incentive, 
Don Miller or anything else. These are unimportant. 
The intentional QRMing that has been going on 
since the FCG acted on incentive does nothing to 
hurt ARRL; it only damages amateur radio. 

I have the very great pleasure to teach an ad- 
vanced theory and CW course for our local radio 
club. It is something that every capable ham should 
try when his time permits. Recently, my students 
have told me that the CW broadcasts sent by W1AW 
have been subjected to an increasing amount of 
QRM. Typically, they reported that the call-up for 
practice <QST de W1AW, etc.) is clear for almost 
the whole of the first five minutes. Then the fun 
begins. 

At first, I was inclined to attribute the com- 
plaints to a lack of receiver selectivity available to 
some of my students. When some of them suggested 
that they were hearing signals zero-beating W1AW, 
I decided to check up on the reports. 

A few nights of monitoring with a selective re- 
ceiver was enough to convince me that something was 
going on. As a result, using an R4A+ Hamscan 
and an SB301+ monitor scope, I have literally watched 
the zero -beating occur and have even copied high 
speed CW QSOs in which the operators seemed to be 
proud of the fact that they were covering W1AW. 
Gentlemen, and I am really using the term loosely, 
how low can you go? There is literally no excuse 
for this behavior. It doesn't help amateur radio a bit 
to keep new hams from licenses or keep those who 
already have tickets from advancement. Besides, it is 
clearly not legal. 

William J. Webster, Jr. WB2TNC/S 
East Cleveland, Ohio 

Bill, if this is really going on, ham radio has reached 
a new low. A tape recording should he made and 
sent to the FCC and their monitor stations alerted. 
The casual QRM on W1A.W is bad enough without 
malicious interference being added. 



Dear 73, 

I think you have the only ham magazine on the 
market. I do wish you would put all adds in a cata- 
log section* I have fussed about this before. 

I sure am enjoying back issues you had on special. 

Orville Gulseth W5PGG 
Clarksdale, Missisippi 

Most advertisers prefer to be separated from the others, 
but perhaps we could convince them if enough read- 
ers voiced an opinion. Let me hnow how you feel 
about having advertising all in one place in the book. 

Dear 73, 

Thanks for the excellent November '67 articles on 
"I. C. Frequency Counter" and "I. C« Pulse Genera- 
tor", Let's have more from W0LMD and W6GXN, 
Please give us lots of digital circuits using the Fair- 
child L C.s (#900, 914, 923) as you have been doing 

Bill Bentley 

Westbury, L. L, New York 

Dear 73, 

The only reason I subscribe to your rag is so I 
won't miss the April issue. Being a long time fan 
of Harvey Kurtzman, I enjoy good satire. MAD never 
had it so good. 

In a more serious vein, I would like to reminisce 
about an experience I had while stationed on Okinawa 
in 1962. 

Being a rather new ham, all starry-eyed and full 
of the - uh - propaganda put out by the League, 
I wrote to them and asked if they could put me in 
touch with fellow League members. I also explained 
that it took about three months for magazines to 
reach the island and was there any arrangement 
whereby they could airmail QST to me. I would he 
glad to pay the extra postage. The letter I got 
back from them said, "Duh, Gosh, I don't know, maybe 
you could contact Okinawa Amateur Radio Club to 
meet some of the fellows". No mention of airmailing 
QST. I sent a similar letter to 73 explaining about 
the delay in getting the magazines, 

I received, shortly thereafter (in a plain wrapper), 
an airmailed issue of 73, and I received them that 
way for the rest of my stay on Okinawa (about 22 
months). I wrote Wayne asking what I owed for 
the courtesy he showed me, but I never received a 
reply. Perhaps it embarrassed him, getting caught out 
of his tough guy act. 

Robert L, Katz WA5CZX 

White Sands Missile Range, New Mexico 

Dear 73* 

I always wondered what Caveat Emptor above the 
ad section in 73 meant until I started studying Latin, 
Perhaps all of your readers who buy equipment from 
this section should get a dictionary of foreign words 
and phrases and look this up, hi. 

Kenneth Bishop WA5MIN 
Victoria, Texas 

Dear 73, 

We have just started the iRadio Club Andino, located 
10,000 feet up in the Andes Mountains ; a group of 
construction men and miners, U.S. and Chilean. We 
are on the air on ail modes 10 through 80 meters. 
CE2RE, CE2AD, CE2RG and CE2RM are all English 
speaking and could show up under the club call of 
CE2SA, Our QSL manager is ex-TG9BC. She hasn't 
received her call yet, but she will see that all club 
contacts Are confirmed. If you want run-down on 
Chile, just QRZ. 

Max Bond CE2RM 
Los Andes, Chile 



FEBRUARY 1968 



87 



Letters 



Dear 73, 

My mail box is flooded with letters wanting- me to 
renew my subscription to your fine publication. This 
warms my soul greatly. Now the last one states, 
"Throw my stencil out and save money", I am so sad 
that you are giving up, as 73 is the best damn maga- 
zine that I have ever received. 

Now, it may be that my friendly postman may be 
high-jacking* my monthly magazine and sending - it to 
his daughter, who is in a home for unwed mothers, or 
the neighbors, who I give TVI to, but somehow we 
have our wires crossed. 

So please check with the quite efficient young thing 
who handles the subscription renewals* and see what 
she has done with my twelve dollar check that I sent 
you on September 21, 1967. This was for a three year 
I'enewal, and I have not received any magazine since 
the one with the cute little "DANGER LAST COPY". 

I already have the cancelled check back and know 
that somehow my name got lost in the pot, so would 
appreciate that you get me back in the groove and 
start the wonderful world of written confusion corning 
to my door again, and if the sweet thing blowed my 
twelve dollars on song, drink, and dance, that's all 
right, just get that 73 back in the mailbox. 

Ray Winstead Evans WA5FDO 
Marmaduke, Arkansas 

Bay, we share, your frustration and that of hundreds 
of other subscribers to 73 at the time we changed over 
to a- new computer. The idea was to take advantage of 
the latest computer techniques for hand ting subscrip- 
tions. This would give us a much more perfect and 
rapid system of handling subs, as well as save us 
enough money to let us ptit off any increases in sub- 
scription rates for a while longer. The "routine change- 
over" went badly. Hundreds got their November issues 
very late, or not at all. Renewal forms tvere sent to 
hundreds of others who had already renewed. Normally 
we expect a, few fellows to get renewal notices after they 
have renewed because it takes a few days for renewals to 
he made and it is not unusual to run off the notices 
during this period. Most subscribers realize this and 
Just throw out the notice, but a few excitable ones 
write to us and Dotty gets a few minutes further be- 
hind checking his subscription to make sure that it 
really is OK, Hopefully, everything will be in good order 
by this issue. We are trying hard to give you the very 
best service possible. We are, by the way, the first ham 
publication to change over to a computer for sub- 
scriptions. 



There hare been hundreds of letters on the AM/SSB 
controversy. However, since Jim is no longer with 
73, I refuse to carry on his battle for him, I think 
there is a place for all modes, and we have to find 
a means of living together in peace. 

Dear 73, 

Have tried TAG and can only say "WOW". My 
question went out and came back like now. Almost be- 
lieve the postman answered it. Thanks. 

Dick Heydt 

_ 
Diet is referring to the Teclmical Aid Group. Else- 
where in this issue you will find a list of the members 
who devote time to answering technical questions from 
the readers of 73. On this score, may I ask that you 
keep a copy of this list handy and refer your queries 
to the appropriate member of TAG rather than to the 
Editor* I would like to be able to help you, but the 
job of production of 73 is a time and a half job and 
I just can't answer each question which comes in. 

Dear 73 T 

Enjoyed KGBIJ's story on underwater radio signals. 
I'm sure it stirred the heart of many ex Sonarmen 
like myself, I served on a DDE for '51 to '55 and we 
had an underwater SSB rig that we could communi- 
cate with subs by either voice or CW, It was called 
the ''Gertrude** for some unknown reason. The official 
Navy designation was something like AN-UQCOL It 
worked quite well and the "antenna" was inside the 
sonar dome beneath the ship. We used to have CW 
drills w T ith other destroyers using it at ranges of 
about 1000 yards. 

Also to kind of answer KGBIJ's question, w T e were 
taught and of course found to be true, that salinity, 
pressure, and density affect sound in water. Sound 
tends to bend away from warm water too, Sound in 
water traveled at about 4800 ft/sec, and increased as 
the salinity and other factors went up. 

Don McCoy WA0HKC 
Wheatridge, Colorado 

Dear 73, 

Please keep up the good articles ! I I dropped the 
other two mags and am reading Tom Swift books in- 
stead, I notice little difference between them and the 
"other two*' ; they're both far-fetched ! 

Thomas Dulisch WA9TDD 
Park Ridge, Illinois 



Dear 73, 

In my opinion the whole controversy engendered by 
Jim Fisk*s article condemning AM is very amusing. 
What both of the warring phone factions seem to 
forget is that there is a simpler, cheaper, and much 
more rewarding mode of operation. While the SSEer 
pays his kiiobuck, and the AMer his centibuck to get 
on the air and fight the QRM, the CW who pays his 
decibuck and sets out confidently to communicate 
farther and faster, and derives much more pleasure 
from cultivating his skill than either of his more 
sophisticated cousins. After all, any boob can talk 
into a microphone. Anybody who says CW is out- 
moded, a waste of time, boring, ridiculous, etc, 
obviously doesn't know what he is talking about. 
When all else fails, my friend, and ham radio has 
lost it's thrill for you, try CW. 

R. T, Wood WA3EPQ 
State College, Pennsylvania 



The Death of Amateur Radio 

Dear 73, 

I have just finished reading the article, "The Death 
of Amateur Radio" from the November issue- I 
wondered if you bothered to do the same? I am very 
surprised to think you would print such trash. 

Richard N. Rurne K3KAW 
Scranton, Pennsylvania 

Dear 73, 

Having read 'The Death of Amateur Radio' by 
WA8FVD, I have some opinions to express. 

First of all, his idea of keeping old AM equipment 
when purchasing new rigs is, in my opinion, absurd. 
Suppose for example, we all kept our old automobiles 
when buying new ones because we might not like 
the prospects of where our old vehicles would go or 
for what they might be used. 



86 



73 MAGAZINE 



The XYL Pleaser Mobile Mount 

The XYL put up with having the rig in 
the car on trips, but served notice she 
wanted nothing left in the car when the 
rig was returned to the shack at the end 

of the trip. 

So— an old U-shaped chassis was found 
which, turned upside down, fitted over the 
hump in the floor boards. Two pieces of 
metal were bolted to it and one of them 
bent upwards to rest against the front of 
the seat cushion. Two notches were filed in 
the end of the upper piece to receive the 
front legs of the SRI 60. A portable speaker 
in a plastic box was wedged on the metal 
platform between the rig and the engine 

firewall. 

It takes only ten minutes to install or 
remove the rig and the only things left 
behind are the power cable and coax, 

. . . Ross A. Sheldon K4HKD 




The XYL pfeaser mobile mount. 



LINE OF SIGHT 

We hear much about the so called "line 
of sight" on UHF and VHF bands but after 
mentioning it, not much more is known; 
especially how to figure it. 

Lets say you have a fifty foot tower on 
the old 2 meter beam. What is your line of 
sight? 50 miles, 25 miles, 10 miles, 5 miles? 

There is a simple formula for calculating 
this distance. It is D( distance in miles) = 
L23VHeight of antenna. The squart foot of 
fifty feet is 7.07. Multiplying this by 1.23 
we have 8.69 which is your line of sight 
from the tower at the antenna. 

Actually the radio horizon is 15£ more 
than this or a total of 9.99 miles. If you 
wish to figure it even more quickly simply 
take the formula of (Distance in miles) = 
V2H, This works out to 2 times your height 
— 100 feet and take the square root of 
that which would be 10 miles. 

This is "YOUR" line of sight. If the 
fellow is on the other end, his line of sight 
is figured the same way and is additive. In 
other words, his line of sight is say— eight 
miles. Yours is ten so you have a line of 
sight of eighteen miles. 

This is why the fellow with the higher 
tower gets out a bit better even though 
he may have the same rig etc. etc. 

(Tongue in cheek) As you raise the tower, 
so do you run up the losses in the coax feed 
line* You can't get something for nothing— or 
hardly, 

. . . Bill Roberts W9HOV 



with a MATERIAL DIFFERENCE! 

Use, is one of the most dependable 

testimonials of endorsement and Tel rex 

products are In use in 139 Lands 



; ( Beamed-Power"ANTENNAS,"BALUNS" 
I. V. KITS and ROTATOR SYSTEMS! 



Most Technically-Perfected, Finest Communication 
Arrays in the World! Precision-Tuned-Matched 
and "Balun" Fed for "Balanced-Pattern" to assure 
'T0P-MAN-0N -THE-FREQUENCY" Results 



Enjoy, World renown TELREX performance, 
value and durability! Send for PL67 tech, data 
and pricing catalog, describing professionally 
engineered communication antenna systems, 
rotator-selsyn- indicator systems, "Baluns" LV. 
Kits, Towers, "Mono-Pole", "Big-Berthas'*, ac- 
cessories, etc., etc. 

Communication 

Engineering 
tf/^^tf laboratories 

ASBURY PARK, NEW JERSEY 07712, U.SA. 




WANTED 

SALES ENGINEERS 
EARN $20,000 per year 

Based on commission from sales and in- 
stallation of just 3 Vanguard TV cameras 
per week! 

Full or Port Time 

Closed circuit TV is recognized as a definite 
necessity for many businesses to combat ris- 
ing costs. Thousands of factories, office build- 
ings, banks and schools will welcome your 
demonstration. 

Using our list of applications as a guide you 
will be able to show how any establishment 
can use several cameras and how each one 
can save thousands of dollars through the 
resulting increase in efficiency and security, 
If you are over 21, have a working knowledge 
of TV and are financially responsible, we 
need you as a sales engineer to demonstrate 
our Model 501 in your area. To receive your 
application and additional details, send us 
a resume of yourself and include a self- 
addressed, stamped envelope. 

VANGUARD LABS 

Dept. H, 196-23 Jamaica Ave. 
Hollts. N. Y. 11423 



SPACE AGE KEYER 




Planar epitaxial integrated circuits for reli- 
ability. No tubes — No separate transistors. 
Precision feather-touch key built-in. 
Fully digital — Dot-dash ratio always per- 
fect. 

No polarity problems — Floating contacts 
switch i-amp. 

Rugged solid construction— will not walk. 
Send QSL or postcard for free brochure. 



Conference. It has been several years since 
IVe had a chance to see all my friends out 
there, so don't disappoint me. 

On June first I will be speaking at the 
Swampscott ARRL Convention and show- 
ing some of my African slides. After being 
excluded for two years from this affair it 
will be nice to get back and see everyone. 

May I caution convention committees not 
to get all excited and expect me to be availa- 
ble. First of all I will be tied down at 73 
for quite a long time to come and it is ex- 
tremely difficult to get away even for a day. 
Secondly, my wife Lin will be coming with 
me anywhere I go, and we just don't have 
the money to make extensive jaunts. The 
bookkeeper complained the other day that 
she needed a bottle of black ink, but that if 
she bought it we would be back in the red 
again. 

( , , Wayne 



BOX 455, ESCONDIDO, CAL 92026 



Our Advertisers 

The advertising in 73 is as important to 
you as it is to us. As IVe mentioned be- 
fore, it is the advertisers that are paying 
for the magazine, since the subscription 
money just barely covers our cost of sending 
out the magazines. If you like a bigger 
magazine then it is up to you to encourage 
advertisers to use 73. We try to run about 
30% advertising, running a little under that 
now and then and a bit higher at times to 
get back even again- This means that every 
page of advertising is bringing you two 
pages of articles. 

You can help us a lot with this. When you 
write to advertisers ordering something for 
heaven's sake please tell them that 73 tipped 
the balance. If you Ve got a gripe tell them 
someone else sent you. 

I know that a lot of you are buying Heath 
equipment, but you sure haven't told Heath 
about it. From now on, when you send an 
order to Heath for something, mark it to 
the attention of Earl Broihier. Earl is in 
charge of advertising up there. Don't let 
me down on this; show him that the 73 
readers are good customers and that you 
want to see more Heath advertising in the 
magazine. Fold down the corner of this 
page so that you can remember to mark your 
next orders to Heath to go to Earl Don't 
forget! 



that one. My head ached and every muscle 
and joint in rny body was wracked with pain. 

By late morning I was feeling a lot better, 
Joe stopped by and we talked a bit more. He 
wanted me to send him some strings for his 
badminton raquet from Bangkok and gave 
me the sizes for clothes for his family so I 
could send some when I got back home. They 
need everything, but clothes are the most 
wanted. 

When the airline bus got me to the airport 
I found that Royal Thai had not notified the 
immigration people about my delay. They 
raised a big fuss over this and seemed about 
to haul me off to jail I got them to tackle 
their phone system and call Royal Thai, They 
finally managed to get through and reluc- 
tantly stamped my passport for the extra 24 
hour visa. 

Burma was certainly interesting, but I 
don't think Til go back right away. A couple 
hours later we landed at Bangkok where I 
was met by John Nolan, a chap who used to 
work for us in Peterborough a couple years 
ago and who at this time was with the U.S. 
Army in Korat, Thailand. He got a couple 
of days off to do Bangkok with me. 

Things are still very rough in Burma and, 
if you ever have a notion to do some good, 
you might just drop a note to one of the fel- 
lows listed in XZ land in the Callbook and 
find out what you can send him that will 
be helpful, Ive been corresponding with Joe 
and have sent over a big box of clothes for 
him and his son. 

Public Appearances 

For the last couple of years I have not 
been at my best and I have thus tended to 
avoid hamfests and conventions as much as 
I could. Til probably be getting out a little 
more this year and I would like to meet as 
many readers of 73 as I can. Say hello, and 
tell me what you think of the magazine * . . 
what would improve it . . . what isn't so 
hot . . < etc. And give a lot of thought to 
ideas for pepping up our hobby. 

First HI be speaking after the dinner 
given by the Northern New Jersey DX 
Association on March 23rd at the Holiday 
Inn, Wayne, N.J. This is at the intersection 
of routes 46 and 23, The program starts at 2 
PM and the banquet at 7. Write W2PXR 
for details and a reservation. Be there if 
vou can. 

On May 11th I will be the guest speaker 
at the Western New York Hamfest and VHF 



X 







VANGUARD ^ Jj/lPiPO 

MODEL SCI SHIPPING COLLECT 

Made In USA. COMPLETE WITH LENS 

SUB-MINIATURE SOLID STATE 

TV CAMERA 

FOR CLOSED CIRCUIT OR AMATEUR TV 

THE VANGUARD 501 is a completely automatic 
closed circuit television camera capable of trans- 
mitting sharp, clear, live pictures to one or more 
TV sets of your choice via a low-cost antenna 
cable (RG-59U) up to a distance of 1000 ft. without 
the need for accessories or modifications on the 
TV sets. The range can be extended indefinitely by 
using line amplifiers at repeated intervals or by 
using radio transmitters where regulations permit. 

There are hundreds of practical uses in business, 
home, school, etc. for any purpose that requires 
you or anyone chosen to observe anything taking 
place anywhere the camera is placed. Designed for 
continuous unattended operation, the all-transistor 
circuitry of the 501 consumes only 7 watts of 
power. 

For complete specifications 
send fat our Illustrated catalog. 

VANGUARD LABS 

196-23 Jamaica Ave. Dept. H Hollis, N.Y. 11423 



WANTED 

MILITARY SURPLUS AS TRADE-IN'S 

WE OFFER new boxed Ameco, Drake, 

Eimac, E-Z Way Towers, Gonset, Ham- 
marlund, Hy-Gain antennas, Ham-M 
Rotors, National, SBE. Sonar, Swan, 
Also reconditioned ham equipment 
taken in as trade. 

WE NEED unmodified surplus equip- 
ment with prefix ARC, ARN, ARM, 
APW APX, APS, APR, BC, FRC, GRC, 
UPX, GPM, GRM, PRC, MD, URM, 
UPA, UPM, URC, USM, URR, VRC, 
TED, TRC, TS, also Bendix, Collins, 
Boonton, Bird, Measurements, ARC, 
GR, Tektronix, Commercial Equipment, 
Collins 18S-4, 17L, 51V, 51Y, 618S, 
618T, 51X, 51R. 51J, and R-278/GR Re- 
ceivers, T-217/GR Transmitters, MD- 
129 /GR Modulators, MT-686/GR Racks, 
AT-197/GR Antennas, Tech Manuals 
and Tubes. 

CLEAN OUT YOUR SHACK by send- 
ing us your list of surplus for trading. 
It might be worth more than you think. 
List what you have and what you 
want. 

Write, Wire, Phone Bill Slep, W4FHY 

SLEP ELECTRONICS COMPANY 

Drawer 178P, Highway 301 

ELLENTON, FLORIDA 33532 

Phone (813) 722-1843 



FEBRUARY 1968 



83 



DON'T QRT! 



LT-5 




$24.00 KIT 

$35.00 WIRED 



When you leave your QTH 
put your LT-5 portable 40-80 
meter CW transmitter in your 
pocket! 

SEND FOR FREE 
DATA SHEET 



OMEGA ELECTRONICS COMPANY 

10463 Roselle St. • San Diego, Calif. 92121 




U I'.KyH-fll.l 



Interested in what 



European hams are 
accomplishing at the 
higher frequencies ? 



/MTSCHRlFf FUflOENVKf UHF flmRTIUH 



Read UKW - BEBICHTE, the authoritative German 
quarterly, now with English summaries! Applications 
of the latest VHF and UHF techniques- equipment and 
antenna construction details. Each sixty -page issue 
packed with practical articles written by the most 
outstanding amateurs in Europe. 

Annual subscription U.S.A. $3.00, Canada $3.25 

H. Ingwersen, FAtfSAFN Box 87, Topsfield, Ma. 01983 

amT^TroTn 

Ferromagnetic Products 

Red "E" Cores — 500 kHz to 30 MHz: 

T-200-2 $3.00 

T-94-2 .75 

T-80-2 .60 

T-68-2 .50 

T-50-2 .45 

T-37-2 .40 

T-25-2 30 

Yellow "SP Cores — 10 MHz to 90 MHz: 

T-94-6 .95 

T-80-6 ,B0 

T-50-6 .50 

T-25-6 .35 

Black "W" Cores — 30 MHz to 200 MHz: 

T-50-10 .60 

T 37-10 .45 

T-25-10 .40 

FERRITE BEADS: Package of 12 

+ Spec Sheet: $2,00 

KILOWATT TOROID BALUN KIT: $5.00 

EXPERIMENTER'S 2 CORE 

TOROID KIT: $1.50 

Minimum Order: ST, 00 
Please add 25c per order 
for packing and shipping 

Ami-Tron Associates 

12033 Otsego Street 
North Hollywood. Calif. 91607 

Courtesy To Distributors 



and you have to worry about stepping in 
strange substances like betel nut chewings, 
little bright red wet splotches that are around 
in profusion, or nice surprises left by rather 
large dogs. 

You don't just in and out of a pagoda. This 
monster was the size of a very large city 
block and had small temples for each area 
of the country, with places to sit, rest, wor- 
ship and even eat. There were all kinds of 
Budhas , . , sitting Budhas, reclining Budhas, 
standing Budhas. The professional prayers 
were hard at work burning candles and pray- 
ing loudly at many of the shrines, pouring 
water over the Budha in the shrine. 

We stopped several times at the Royal 
Thai Airline ticket office to make sure that 
my flight out was going to be on time. The 
fellow in charge unfortunately couldn't speak 
English so we had a little problem. He tried 
several dozen times to get in contact with 
the airport by phone, but the telephone serv- 
ice is run bv the army with the same efficien- 
cy that they run everything else and it wasn't 
until about noon that we finally made con- 
tact. My flight had been cancelled and Roval 
Thai would see that my visa was extended 
one more day. They would also pay my 
extra day of hotel and meals. 

This was nice, but I was feeling more and 
more ill and I was not at all anxious to come 
down with something serious in a country 
which had hospitals run like the telephone 
service. I had the distinct impression that they 
might just ship me out of the country on a 
stretcher, if this was where I was when my 
plane left. I would much rather get sick in 
friendly Thailand. 

I managed to last through a nice Chinese 
lunch with Joe and a visit to the Rangoon 
zoo, but I was weakening badly when we 
went to an afternoon billiard tournement. I 
did have an opportunity to talk with a chap 
from the British embassy who backed up 
everything Joe had told me about Burma. 
They wanted to take me out to dinner after 
the match, but I was about ready to pass 
out and just got back to the hotel in time to 
drop into bed for the night. I couldn't even 
eat the free Royal Thai meal. 

During the night I was violently sick, com- 
plete with a raging fever and icy chills. There 
were two beds in my room and I put all the 
blankets on one and crawled underneath to 
shiver. The room was about 90°. When I 
soaked the bed completely I moved the 
blankets over to the second bed and used 






a bicycle he can get a ration book for it 
which permits the purchase of one tire per 
year at about $40. 

Joe pointed to the receiver up on a shelf 
and said wistfully that he tunes twenty meters 
now and then just to listen in. There seems 
little hope that amateur radio will be per- 
mitted again in Burma for a long time* He 
saw that I was having trouble believing that 
things were so bad in Rangoon and said 
that he would take me on a short tour of the 
town when he drove me back to my hotel. 
The car? Well, the army used it until it fell 
apart and refused to run any longer and then 
returned it. He and his son managed to get it 
working again and kept it just barely running 
so they wouldn't take it back again. 

We drove through Rangoon at 10 pm and, 
as he said, everything was closed. Everything. 
I explained that I had to catch a flight out 
the next afternoon since it is impossible to 
get more than a 24 hour visa. Joe said he 
would show me the town in the morning so I 
could see for myself what it was like these 
days. 

When I asked him about Don Miller's visit 
and how Don had managed to stay in the 
country for two weeks and get permission to 
operate when the locals were not allowed on 
the air, Joe said that as far as he had heard 
from the other hams in Burma Don had never 
been there. They had heard about Don's 
"Burma" operation, but were quite sure that 
he could not get a license or be permitted to 
bring any equipment into the country. Also 
there was virtually no way to overstay a 24 
hour visa without going to jail. He said that 
the Burmese hams were convinced that Don 
had operated from somewhere else, probably 
Thailand. 

The next morning Joe drove up to the 
hotel in his jalopy and picked me up for the 
grand tour. Sure enough, as he had said, al- 
most every store and factory in the city was 
closed tight with barred doorways. The main 
department store for the city (run, like every- 
thing else, by the army) had virtually no mer- 
chandise. The little government food stores 
had small dirty boxes of the grimiest rice and 
beans you ever saw, and little else. 

Next we started on the pagodas. The big- 
gest one is right in the middle, of town and 
it is a corker. The big problem, for a tender- 
foot like myself, is that you must remove 
your shoes to visit the pagodas. This is no 
problem if your feet are accustomed to walk- 
ing on tiles that are baking in a tropical sun. 




3V4" x Vz" RACK PANEL 

10" Depth $5,00 PPD 

Check or M.0, No COD 

NYC R&s, Add 5% 

NYS Res, Add 2% 

DEVICES 



CONSTRUCT YOUR 
EQUIPMENT THE 
EASY WAY— USE 

THE UNIT CHASSIS 

Wire and test the subehassis out- 
side where everything is acces- 
sible. Assemble the subchassis 
into the unit chassis and you 
have a professional package. 



3" x 61A" 
sshchtssif 




BOX 136 BRONX NX 10463 



JUNK BOX ANEMIC? 

We have a cure — electronic parts, hardware, lubes, assem- 
blies and such for sale by the pound. The parts are un- 
used or removed from new equipment. Limited supply: 

IT pounds $ 3.00 Plus postage for 21 pounds 
100 pounds $14.95 F.O.B. Bluff ton, Ohio (truck shipment) 
We also have a number of part assortments listed in our 
"Free" catalog along with regular electronic parts and 
toots. Just a post card will do, but list your zip code. 

BIGELOW ELECTRONICS 
P.O. Box 71, Dept. 73 B, Bluffton, Ohio 43817 



I 



oscillator/monitor 

• a seniitive broadband RF detector 
gives audible tone signal in the 
presence of any RF field from 10m w 
tot kw and TOOkc to lOOOmc 

• a CW monitor with positive "tF 1 * 
twitch uses only 8" pickup antenna 
and NO connection to rig or key 

• a code practice oscillator with 
adjustable tone & built in speaker 
a high gain 4 transistor circuit 
powered by long life AA pencell 

• 16gauge aluminum cabinet in 
white & black epoxy finish, 3 V2 " 
by 2 Vi " by 1 1/4 ", weight 8 ounces 

• 100 % US made and guaranteed 

the James research company 
IT schermerhorn st v Brooklyn ny. 11201 




1 O 95 (batt incl) 
I JLm ppd usa eVcan 
fend cert ck or m.o. 
ny res add 5% fax 



R19/ARC12 — 118 to 148 mc Tunable Receiver 
complete with 9 tubes and schematic. . $29.95 

DAVEN Frequency Meter — Direct indicating fre- 
quency meter covering 25 to 5000 cycles in 
four ranges (.1-.5-1-5 kc). Exc. Con $29.75 

Ha I lie rafters — HA12A Encoder, New $7.50 

Panada pter 

IP-274/ALA — See June 1964 73- Furnished in ex- 
cellent condition with tubes and conversion 

*-J cj L Cj ..... ........ .... .i.i«iittlf**#* HP * -£►■* J J 

R10/ARC12 — Broadcast Receiver $19*95 

RTTY Discriminator 

Sub unit for frequency shift converter CV-89A/ 
URA8A. New . $34.50 

Send for Catalog #132 

ARROW SALES-CHICAGO, INC. 

2534 S. MICHIGAN AVENUE 
CHICAGO, ILLINOIS 60616 




U. S. CRYSTALS 

Surplus Crystals — Amateur 

FT243, DC34 F CR1A/AR, FT24I. 
HC6/U and other misc. crystals 

Write for Fr^e CatalQQ 

U. S. CRYSTALS 

P.O. lax 78397 

Los Angeles, Calif. 



1 






ELECTRONIC/COMMUNICATIONS SLIDE RULE, 

"Ricoh" Model 156LAI computes L, C. F , X c , Xi, 
-£ db, and many other most used formulae in 
three settings or less* Seventeen red or black 10" 
scales (±db t DF, CF, GIF, CI, C, D, A, Xc f Xi t K, 
KI, S, T\ Fi, Ft% DI) engine engraved on hard 
glare-free white plastic, bonded to warp resistant 
laminated bambo. Accessories: Genuine leather 
case, plastic decimal point table, instruction 
booklet. Made in Japan. Save $9.00!) Cash price 
prepaid to any US post office . * . $15.95! Yukon 
Electronic Sources, INC., Drawer "0*\ College 
Alaska 99701. 

9y 2 by 101/2 CLOCK CONVERSION CHART. Heads 
all times at a glance, a must for every ham 
shack. Only .75 check or M.O. only. J\ F. Siemiet- 
kowski, 3039 East Thompson St., Phila., 19134 
Penna. 

IDEAL COMPANION FOR HT-44 Hallicr afters 

SX117, receiver. Needs slight repair, $225 or best 
offer. Rota Martin WB2WBA, Box 36. Katonah, 
New York 10536. 

GOODIES, cash for Teletypewriters, parts. List, 
Sell 14s t 15s, 19s, 28s, parts, Toroids, 6/$2 post- 
paid. Typetronics, Box 8873, Ft, Lauderdale, Fla. 
33312. 

HALLICRAFTERS SX140 Novice receiver, 80-6 
meters, $65 shipped in continental U.S. Heathkit 
DX-100, good condition, FOB Lynn Ziegler 
WA5LTC, Route 3, Denison, Texas 75020. 

HEATHKIT SENECA VHF-1, six and two meter 
transmitter, looks and operates fine r only $145,00. 
K1PNI, 133 Larchmont Road, Warwick, RJ. 02886. 

POWERSTAT, type 136, 20 amps, brand new, in- 
cludes triplet 0-150 vac meter, only $30.00. K1PNI, 
133 Larchmont Road, Warwick, R.I, 02886. 

EICO 720 perfect $60. 75A-2 $175. ART-13 nice un- 
modified $25. K8ZID Henry S. Allgyer, Gnaden- 
hutten, Ohio 44629. 614-254-4172. 

HY-GAIN 153-B full size three element 15 meter 
beam f $22.50, Also BC-696A $12.50. W6IH, 12252 
Hartsook St., No. Hollywood. Calif. FO 1-8979. 

^ 1 

HW12, 22, 32, OWNER ("A" SERIES ALSO): Con- 
vert your rig to three bands with SSB Sc CW 
coverage. Send $3.95 for assembly manual or 10<* 
for illustrated brochure. DRC. 215-28 Spencer 
Avenue, Queens Village, New York 11427, 



HR060 100 ke-54mc,spkr, S289; HQ-180C. spkr. 
$169; HC-10 SSB converter $100; all like new. 
T\ C. Howard, 46 Mt, Vernon St., Boston, Mass. 
02108. 



WANTED: R-390A/UBR. 51J-4, R-388, Model #28 
Teletype, etc. Cash or trade. Alltronics-Howard 
Co., Box 10, Boston, Mass. 02101 (617-742-0048). 



STEP ATTENUATOR, Kay 432d, precision, 
-0-101db in 1 db steps, 50 ohm. good to 500 MHz. 
$50 ppd* Herbst, 2F, 3001 Edwin, Fort Lee, N.J. 
07024. 



6 METER CONVERTER, 3 FET transistors. 
Printed circuit board construction, 14MCs output, 
less power and xtaL $8.50 FOB. Bill Dearie, 8831 
Soverign Rd. f San Diego, Calif. 92123. 



TELETYPE TEST SET I-193C. Brand new surplus. 
Tests RTTY transmitters, converters, relays, S24.95, 
F.OB. Harrisburg, Pa. Telemethods International, 
P, CX Box 18161, Cleveland, Ohio 44118. 



ARNOLD'S ENGRAVING 

Personalized 




Works on 110 VAC— $10.95 



WA2ZHA 



Metallex lapel bar— $1,50 or Tie Clip— $2.25 

ARNOLD LINZNER 



204T Linden St. 



Ridgewood, N.Y, 1122? 




I 



! 



®TVfuvurm» 
tcatL 144* 



*§y" 



TTFtfT 1MB tr 




TUNAVERTERSII 

10 to 2 meters for HP 
& VHP AM-FM Marine, 
SW. and Police, Fire, 
etc! Tunable RF con- 
verters. 

For all auto and home 
radios! Transistor & 6-1 
tuning I 
Jan. 'o8 73 ad page 81) 



(See Complete listing In 

Dept, 7?, Woodsboro, Texas 78393 
HERBERT SALCH & CO. 



I 



DON'T ASK! TELL US! 

If you have any Sen. Radio, H-P, Tektronix 
and other military and commercial gear to sell, 
tell us flat out what you want for it! You call 
the shot! 

You name your own price for your ARC, GRC, 
TED, PRC, VRC, ARN, URR and AP'N equip- 
ment. No matter what others promise, we 
guarantee to pay more for it! BUT YOU 
GOTTA TELL US TO SELL US! Write, ca 
cabfe or telegraph today! 

COLUMBIA ELECTRONICS, Dept. 7 

4345 W. Pico Blvd., Los Angeles, Calif, 90019 
Phone: (213) 938-3731 Cable: COLECTRON 



1 
i 

i 
i 
i 
i 
i 



BUILDERS NOTICE 

If you like to design and build with transistors, we have 

the following components packaged up as assortments. These 

kits are excellent for value and quality. You will truly he 

pleated* 

I Transistor & rectifier mounting hardware for T03's, 

T05"s. TOO'i, TOfifi's, etc ,, $1-50 

H Spagetti tubing, plastic, cambric. Temflei, Teflon, over 
100 ft all sizes you need $J,95 

III 50 transistor electrolytic^, p.c. and axial lead types, as- 
sorted sizes and voltages. Fresh stock. If you build you 
need them . . $4,50 

IV Volume and squelch controls, panel mount, asst 

One each of above kits— -1-2-3-4 . ... $8.00 

U5v tine cords TJh APPB, 6 ft *.,*..«. S for $,95 

Sarkea Tarzian IN3O20A lOv-lw Eerier 55c 2 for $1.00 

NEW — These transistors are factory firsts, brand name 
&N2671 PXP trans. Amperes mix/rf shielded case 

4*Iead FT 100 tnc $,50. 12 for $4 
2N2QS0 PNP Amperex rf/osc/mix FT T5 me, case 

lead terminated. $.40 each, 12 for $3,50 
2Nl52ft PNP RCA osc FaB 33 mc. Use as funda- 
mental tal osc. $.35 ea., 12 for $3.25 
2X1524-1525 PNPs, i.f. ,... $,35 ea., 12 for $3,25 

922-24 Elm St., RACINE, WISC. 51403 
TOWER COMMUNICATIONS 



FEBRUARY 1968 



93 



B-C FLIPS THE LID ON SURPLUS 

TV-IG/UHF-VHF transvertflr, S channel crystal controlled 
AllC-12 transmitter, 228-258 mc and receiver -converter, con- 
verts Incoming 328-258 mc to 118-148 me to feed Into K-1&/ 
ABC -12 receiver,, using 110 nic crystal oscillator. NEW, 
with instruction book* » ,.,,***»** t ...*..,., * , $35.00 



RllA/AHC complete with all tubes, has 
hi-Q ceramic 85 kc i-f J s (see Sept. 1963 73 
"Q-5er Reborn"). Very excellent used 

( J ^ ) ,,>,.. t M M M I V> • , i I I 4 1 I H I I 5l33 




*:* 




used 



m IP274/ALAI0, 2 meter panoramic adapter, 30 mc ± 

* 5 mc input, 400 cy power supply with instructions 

for solid states 60 ey supply and to 14 mc input 

; Internally complete, 3BF1 & 17 tubes, Excel, (45) 

1 Reduced to close out , ....*.*. « $1 5.00 

MN-26LB, Bendlx direction finder & communi- 
cations receiver. 3 band, 200-410, 550-1200 ke, 
2.9-0 mc. Internally complete, 12 tubes. Excel. 



(40) ., 
2f)D loop 



■ 




$12.95 
antenna for above, not rotable. NEW ...,$1.95 

Lazy Man's G-Ser, 1020 cycle filter, 3 position 
switch-RANGE passes 1020 cycle YOICE re- 
jects 1020 cycles, both no filtering. A "MUST" 
for CW & Teletype, Lowest price, NEW 
(S) .,.$2.25 

WESTON model 742, AC /DC mirror scale, 
accurate voltmeter. I>C scales 0-30 & 
0-300 v. AC scales 0-1.5, 0-15 & (M50, 
4%* square, provision for edgelighting; 
complete with all necessary multipliers, 
on an assembly 1 ma DC basic move- 
ment. BRAND NEW $20.00 

Hamfest schedule: Wheaton $wapfest, 
Du Page County Fairgrounds, Feb. 18th. 

All orders, except In emergency, or I'm at a hamfest, 
shipped same day received. For free * T GOODIE' J sheet, send 
self- addressed, stamped envelope— PLEASE, PLEASE Include 
sufficient for postage, any excess returned with order, I carry 
private (Travelers) parcel post insurance,, for domestic parcel 
post. For items too heavy, or too large for parcel post, 
I suggest bus parcel express. Please advise name of bus 
line, and city, where you can pick up the shipment. 
Canadian customers — PLEASE add sufficient for postage — 
SI. 00 first two pounds, 30c each additional pound or fraction. 

B C Electronics 

Telephone 312 CAJumet 5-2235 
2333 S. Michigan Avenue Chicago, Illinois 60616 




S S B ■ s— SWAN 500' s 
NOW IN STOCK— $495.00 

KWS-1 $795. Tlking 500 1375. 

KWM-2 ,.• 795. NCX-3 199. 

Poly-Comm 62 ...... 225. Eico 753 ... 159, 

LARGE STOCK OF USED EQUIPMENT ON KAND 

FRECK RADIO & SUPPLY CO., INC. 

38 Biftmore Ave., Ashevilie, N. C. 28801 
Ph. 704-254-9551 CLOSED SATURDAYS 

T. T. Freed, W4WL Sandy Jackson, WN4AAL 



A5 



AT VERS 



For the largest US ATV magazine; 

Technical reports & ATV directory 

SEND $1 for special Introductory 
($2 after March First) 

I year subscription TO: 

MAGAZINE Dumont, NJ 07628 



LEARN RADIO 




Album eftntallit three 12" 
LP'i 2Vk hr. Instruction 



THE EASY WAY! 

• N« B««ks T« Read 

• M* Visual Gimmicks 
T* Distract Yaw 

• Just Listen And Learn 

Based on modem psychological 
techniques— This course will take 
you beyond 13 w.p.m. In 
LESS THAN HAIF THE TIME) 

Also dvailable ort magnetic tape. 
See your dealer now) 



EFSIL0N C£] RECORDS 



206 East Front Stew), Florence Colorado 



WANTED: Record, tape, or lyrics of the song 
"Gloomy Sunday" from the early 1930 era. 
W0HJL r P. O. Box 224, Dublin, N,H. 03444. 

WANTED: TEST EQUIPMENT, laboratory quality 
such as Hewlett-Packard, General Radio, Tek- 
tronix, etc. Electronicraft, Box 13, Ringhamton, 
N.Y. 13902. Phone (607) 724-5785. 

MOTOROLA new miniature seven tube 455 kc if 
amplified discriminator with circuit diagram. 
Complete at $2.50 each plus postage 50c each 
unit. H and R Electronics, 1953 South Yellow- 
springs, Springfield, Ohio. 



TOROIDS— DIODES — COAX — CONNECTORS. 88 

mH toroids— 45^ each, 5/$2, 00. 1000 PIV 1 Amp 
Top-Hat Diodes — 55tf ea. 2/$l,00. Connectors, 
PL259, SO-239, M359 — 45£ ea. 10/J4.00, Button feed- 
throughs (while they last) 500 pF § 500 V. 
20/$1.00. Add sufficient postage. R and R ELEC- 
TRONICS, 1953 S. Yellowspring St, Springfield, 
Ohio. 

VARIACS — General Radio and Ohmite. 60 cycles 
Input 120V— output 0-280 V. 1 amp or input 240 V 
—output 0-280 V. 2 amp, PtfLLOUTS IN GUAR- 
ANTEED EXCELLENT CONDITION $6.95 plus 
postage. Shipping weight 10 lb, R & ELEC- 
TRONICS, 1953 S. Yellowspring St., Springfield, 
Ohio. 



WANTED: Military, commercial, surplus, Air- 
borne, ground, transmitters, receivers, testsets, 
accessories. Especially Collins. We pay freight 
and cash. Ritco Electronics, Box 156, Annandale, 
Va. Phone 703-560-5480 collect. 

WANTED: Tubes, transistors, lab instruments, 
test equipment, panel meters, military and com- 
mercial communications equipment and parts. 
Bernard Goldstein, Box 257 Canal Station, New 
York, N.Y. 10013. 



BUYS from America's smallest ham dealer. 
Jerry Hirsch has all major brands and needs 
used gear, big trades call me last! Hirsch Sales, 
219 California Dr., Williamsville, N + Y. 716-632-1189, 

RTTY GEAR FOR SALE. List issued monthly, 88 
or 44 MHy torroids 5 for $L5Q postpaid. Elliott 
Buchanan & Associates, Inc-, 1067 Mandana Blvd., 
Oakland, California 94610. 

LAWTON-FORT SILL HAMFEST— February 11, 
1968. Contact David R. Tancig, WA9FRE/5, 1923 
Kinyon, Lawton, Oklahoma 73501. 

DUMMY LOAD 50 ohms, flat 80 through 2 meters, 
coax connector, power to 1 kw. Kit. $7.95, wired 
$11.95, pp Ham KITS, Box 175, Cranford, N.J. 

COPPER CIRCUT BOARD Epoxy glass base l 1 * 
x SVz single sided 3 oz. copper. §1.00 ea,, two for 
$1,50 postpaid. Electrographics, 2440 Wildoak 
Drive, Dallas, Texas 75228. 



CLUB SECRETARIES NOTE 



Club members would do well to get their club 
secretaries to drop a line to 73 and ask for the special 
club subscription scheme that we have evolved. This 
plan not only saves each club member money, it also 
brings badly needed loot Into the club treasury, if de- 
sired. Write: Club Finagle, 73 Magazine, Peter Boro 
Ugh, New Ham Shire 03458. 



* TRANSISTORS * SOFTS * ZENERSIM 
Full Leads Factory Tested & GTD! 
PNPIOO Watt/15 Amp HiPwr T036 Case! 
2N44I, 442, 277, 278, DS50I Up To 
50/VCBO Sf.25f$, 5 for $5 
2N27S, 443, 174. Up to 80V $3@, 2/$5 

We Buy! We Sell! We Trade! 

PNP 30 Watt/3A, 2NIF5, (56, 235, 242 
254, 255, 256, 257, 301, 392, 40*@ 3 for $1 

PNP 2N67O/3O0MW 35c@ 5 for $ I 

PNP 2N67I/I Watt 50c@ , ...4 for $f 
PNP 25W/TO 2NS38. 539, 540 ,.2 for $1 

2Nr038 6/$l t 2NI039 ... 4 for SI 

PNP/T05 Signal 350MW 25e<S>, 5 for $( 
NPN/T05 Signal IF, RF, OSG 

25cS) 5 for $ I 

Finned Heat Sink 180 SQ". $l.50@, 4/$5 

Finned Sink Equtv, 500 SG" 2/$7 

SILICON PNP/T05 Sl TOI8 PCKG 
2 N 327 A. 332 to 8, 474 to 9* 541 to 3, 
935 to 7 & 1276 to 9, 35c@ .._,.. 4/$l 

Send 25 c for Catalog 

Discaps .OOIOIOOOWVDC (Oc® ..20/SI 
Discaps 2X + O04@!0O0WVDC I5c@, 10/51 
Discaps .03 ci> I000WVDC IScfoo . . I0/$I 
Discaps .0l@20Q0WVDC I8e@ . ..6/$J 

Diseaps .0OI@)5KVWDC 20c@ 6/$l 

€ or J2VAC Minifan & Blade $1 

T03/PIN LUGS for R & E .,> 5/$ J 

TOP $$$ PAID FOR 304TL TUBES 

18 Pressfit Diodes to 100 Piv 5/$t 

MICRO-MUSWITCH 35A AC/DC, 5/SI 
2N408 RCA SHORT LEADS, 5 for $1 

Silicon Power Diodes, Studs & P.F. 



D. G, 

Amps 

12 

** E8 

45 

160 

240 

D. C. 

Amps 
12 
18 
45 
160 
260 



## 



50PJV 


(OOPiv 


200PIV 


35Rms 


70 Rms 


l40Rms 


.25 


.50 


.75 


.20 


.30 


.75 


.80 


1.20 


1.40 


1.50 


2.00 


4. • / J 


3,75 


4.75 


7.75 


400Piv 


GOOPiv 


700Piv 


280 Rms 


420 Rms 


490 Rms 


1.20 


1.50 


1.75 


1,50 


Query 


Query 


2.25 


2.70 


3J5 


4,75 


6,00 


7.75 


14.40 1 


19.80 


23,40 



300Piv 

2tORms 

,90 

1.00 

1.90 

3.60 

10.45 

900Piv 
630RmS 

2.50 

Query 

4.00 

10.00 

Query 




SCR -SI L ICON -CONTROL RECTIFIERS I 



PRV 

50 

J 00 

200 

300 



ISA 
,70 
.05 

1.15 
1.40 



1.00 
[.20 

J. 30 

r.65 



PRV 

400 
500 
000 
800 



ISA 
1.60 

1 .90 
2.30 
3.30 



25A 
2.00 
2.35 
2.90 
4.40 



2 RCA 2N408 & 2/IN2326 Ckt Bds 
IN2326 Can Unsolder 10 for $1 



Glass Diodes IM34, 48, 60, 64, 20 for $1 

MICA MTG KIT T036, T03 TO10 4/$l 
ANODIZED "TO" INSULATOR ..,.5/$l 

ZENERS I Watt 6 to 200V $1 Each 

ZENERS 10 Watt 6 to 150V.. $1.25 Each 
STABISTOR up to Ten Watt -.10 for $1 



SU4 Silicon Tub© ...$2@, 3 for $ 5 

5R4 Silicon Tube $5@, 2 for S 9 

866A Silicon Tube ..$I4£), 2 far $24 



TAB" * SILICON ONE AMP DIODES 

Factory Tested & Guaranteed 



Piv/Rms 

50/35 

.05 


Piv/Rms 

100/70 

,07 


Piv/Rms 

200/140 

.10 


[ Piv/Rms 

300/210 

.12 


400/280 
.14 


600/420 
.21 


800/560 
,30 


900/630 
.40 


1 000 /700 
.50 


1100/770 
,70 


1 700/ 1 200 
1.20 


2400/ 1 68 
2.00 



1700 Piv/1200 Rms @ 750 Ma. JO for SI0 
2400 Pi v/ 1 680 Rms @ 750 Ma. 6 for $11 

*All Tests AC & DC & Fwd & Load! 
Wanted Trans istors, Zeners, Diodes! 



W 



Buy, Sell & Trade As Well! 

TERMS: Money Back 
Guarantee! Our 24th 
Year. $5 Min. Order 
F.OB. N, Y, C. Add 
Shipping Charges. 
Ill HB LIBERTY ST.. N.Y.C. IOO06 N.Y. 
PHONE 732-6245 
Send 2 5c For Catalog 



"TAB" 



Toroids 88Mhy New Pckg 2 for $1 

200 KC Freq Std Xtals $l.50@, 2 for $2 
2 Side CU Printed CKt Bd New 9x1 2" $1 
Klixon 5 A Reset Ckt Breaker $l@, 10/ $5 
ZK to 8K Headsets Good Used S3@>, 2/15 
Finished Pieio Xtal Blanks ..25 for $1 
Resistor Bleeder 50K/I0OW ...,2for$l 

RUSH YOUR ORDER TODAY, 
QTYS LIMITED 

X-Formers All l\W-6QCy Primary — 

2500® lOMa & Fil $2@ 3/$5 

IIOOVCT® 30OMa. 6V@) 8A, 5V @ 3A &. 

125V Bias, abt I200VDC $5@, 4/$t5 

2.5V© 2A $l@ 3 for $2 

6.3V@ J A $L5"Q@ .... ....4 for $5 

20VAC & TAPS/8, 12, 16, 20V@ 4A $2@ 
32 VCT/IA or 2XI6V@ IA $3® 
880V Vet @ 735 Ma for SSB $I2@, 2/$22 
480 Vet® 40Ma &l 6.3@ I.5A CSD $1,50 
10 Vet@ 5A & 7.5 Vet © 5A .,......$5 

6.3 Vet@ I5.5A & 6.3Vct@2A ..$5 



866 C.T./2.5V/1QA FILAMENT 
XFMR 10 Ky Insitd SPECIAL $2 



Bandswitch Ceramic ikw 2P/6Pos $3@> 

5 Hy-400Ma Choke $4@ .2/$5 

6 Hy-500Ma $5<S> 2/$G 

250Mfd(«)450 Wv Lectlytic $3@, 5 for $10 
Cntfsr Oil lOMfd x 600VOC 75c@, 10/$5 
Cndsr Oil 6Mfd @ 1500V $40. 5 for $10 
Line Filter 200 Amp/ 130V AC $5, 5/$20 
DC 3'/*** Meter/ RD/800 Ma $4@, 2/$7 
DC 2Vz" Meter/RD/100 Ma $3@ 

Heiipots MuLti Ten»Turn@ $5 

Helipot Dials $4@, 3/510 

Socket Ceramic 1625 Tube 3/$l, 8/$2 

Socket Ceram c 866 Tube 4/$l, I0/S2 

Socket Ceramic 4XI50/Loktal 4/$2 

XMTTG Mica Condsr .0060) 2.5Kv 2/$l 
Minl-Rectifler 25Ma/l I5VDC/FWB, 5/$l 
W.E. Polar Retay#255A $5@, New 2/$9 

2.5MH Piwound SOOMa Choke 3/fl 

Knob Spin-Crank BC348 $1 each ...S/f2 
MtniFan 6 or 12 VAG, $1.50 each . .4/$5 

Beam Indicator Selsyns 24VAC 2/$7 

Teletype TLI47 Feeler Relay Gage . ...$l 
Fuse 250MA/3AG 50/$l, 30O/$2 

TRANSISTORS, DIODES, ZENERS 



Send 25c for New Catalog 



GOTHAM'S AMAZING ANTENNA BREAKTHRUH 

How did Gotham drastically cut antenna prfces? Mass purchases, mass production, prod- 
uct specialization, and 15 years of antenna manufacturing experience. The result: The 
kind of antennas you want, at the right price! In QST since '53. 



QUADS 



Worked 42 CflliritrffS ill Hvn 
weeks with my Gotham Quud 
and only 75 watts . . - W3AZR 




* 



: 



CUBICAL QUAD 

ANTENNAS — 
thefiu two clt'int'iit 
bt; :i ms hare ;i full 
w^vi'U'tiftth driven 
clement and n fe- 
ll tictor; the dnin is 
equal to th:tr of 
a three element 
beam umi the di- 
rectivity nppetira 
to U9 to be excep- 
tlonul! ALL METAL {except the insula- 
tors} — absolutely no bamboo. Complete 
with hoom t til um ilium ulloy sp rend era; 
sturdy, imiver&al-type beam mount; uses 
single 52 ohm conxiiil feed; no slabs or 
m^ichiaC devices needed; full Instruction 
for the simple one-man assembly and 
installation ;ire included; this Is a fool- 
proof beam that always works with ei- 
ceptioual results. The cubical quad in the 
antenna used by the DX champs /and it 
will do a wonderful job for yon J 

10/15/20 CUBICAL QUAD SPECIFICATIONS 

Elements: A full wavelength driven ele- 
ment and reflector for each band. 

Frequencies: 14-14*4 Mc.; 21-21*45 Mc. p 
25-20.7 Mc, 

Dimensions: About 16' square. 

Power Rating: 5 KW. 

Operation Mode: AIL 

SWR: 1.05:1 at resonance. 

Boom: 10' X i'/i" OD, IS gauge steel, 
double plated, gold color. 

Beam Mount: Square aluminum alloy 
plate, with four steel U-boit assem- 
blies. Will support 100 lbs.; universal 
polarization* 



BEAMS 



Trie first uiriamiK I put up my 
,1 clutH'tu (rnil^nn !>L!;nn i20 I l j 

i worked ytucr. OSMAW 

SP<JADy, ami 4C11TU. THAI 
AXTKXN A W )KKS [ WNM \)YS 




Compare the per- 
form an qe t valuer 
and price of the fol- 
lowing U earns and 
you will see that 
this offer is unprece- 
dented in radio his- 
tory J Bach beam is 
brand newt full aize 
(3&* of tubing for 
#aeh 20 meter ele- 
ment, for instance) £ 
absolutely complete including a boom 
and all hardware; uses a single 52 or 72 
ohm couxiul fecdline; the SWR is 1:1; 
easily handles 5 K.\V;y s "uiifl 1' aluminum 
alloy tubing Is emptoye<L for maximum 
strength and low wind loading: all beams 
are adjustable to any frequency in the 
band. 



2 El 20 $16 

3 FJ 2ft . . . , 22* 

4 El 2ft 32* 

J El 15 12 

3EI15 16 

4 El IS . , 25* 

5 El 15 2fi* 



4 El 10 SIS 

7 El 1ft 32* 

4 EL 6 ... , 15 

«KI6 28* 

11 El 2 25* 

*20' boom 



* f diameter* 
X 1" OD alu- 



Radiatin^ elements: Steel wire* tem- 
pered and plated, .064 

X Frameworks: Two 12 J 

minum 'hUstremUh' alloy tubinft # 
with' telescoping %" OD tubing and 
dowel insulator. Plated hose clamps 
on telescoping sections* 

Radiator Terminals: Cinch-Jones two- 
terminal fittings. 

Feed line s (not furnished) Single 52 ohm 

coaxial cable. 
Now check these startling prices — 



ALL-BAND VERTICALS 

"All band vertical T* asked one 
skeptic. "Twenty meters is murder 
these days. Let's see you make a 
contact on twentv meter phone 
with low power r So K4KXR 
switched to twenty, using a VS0 
antenna and 35 watts AM. Ilere is a 
small portion of the stations he 
worked : YEJFAZ, T12FGS, W5KYJ. 
WtWOZ, W2QDII, WA3DJT, WU2- 
FCb\ W2YHH, VE3FOJJ, WA8t:ZE, 
KlSYit, K2RDJ, K1MW, KSHCY, 
K3UTL, W8UJC f WA21A'E t YS1- 
MAM, WAHATS, K2PGS, W20Jl\ 
W4JWJ, K2PSK, WAUCGA, WB2- 
KWY, W21WJ, VE3KT. Moral: It's 
the antenna, that counts? 

FLASH! Switched to 15 cw. and 
worked KZ5IKN, KZSOWN, HCl- 
LC, PY5ASN, FC7XT, XE2I, KP4- 
AQh, SM5UGK t G2AOB, YV5CLK, 
OZ 411, and over a thousand other 
stations ! 

V40 vertical for 40, 20, IS, 
10, 6 meters. . _ .514.95 

VSO vertical for 80, 75, 40, 
20, 15, 10, 6 meters. $16.95 

V160 vertical for 160, SO, 75, 
40, 20, 15, 10, 6 meters. . . $18.95 



note that they are much tower than 
even the bamboo -type: 

10-15 20 CUBIC! AL. QUAD *3S.« 

10-15 CUBICAL QUAD . ., ..♦«., 3G.00 

15-20 CUBIC! AL QUAD 32. 00 

TWENTY ME TER CUBICAL QUAD . 25.00 
FIFTEEN METER CUBICAL QUAD . 24.00 
TEM METEH CUBICAL QUAD 23.00 



(all use single coax feedlint" 

How to order: Send check or money order. We ship immediately upon receipt of order 

by railway express, shipping charges collect. 

GOTHAM, 1805 Purdy Ave, Miami Beach, Fla. 33139 






From the birthplace of the greatest inventor of all ages, Leonardo Da Vinci, comes 
this made-in-ltaly — world's most practical for the price, 



L 



PRESTEL FIELD STRENGTH 

Calibrated from 40 to 860 Megahertz, from 10 to 
50,000 Microvolts. Nothing makes !t easier to 
properly and speedily find the correct place to 
install TV, FM and Communication Antennas. You 
can measure and hear the signals with this 4^2 
volt battery economically powered unit. There is 
nothing else like It! 

OnlyJ mOO 

" ., j 

We continue to purchase FOR PROMPT CASH j 
small and large inventories of electronic equipment, ' 
tubes, semiconductors, etc. 

Wire, write, phone co/(ecf I 
We pay freight on all purchases/ 




(Model 6T4G) 



j^« 




Liberty Electronics, Inc. 

548 Broadway, New York, New York 10012, Phone 212-925-6000 



0U7 



OFFERS 



INDEX TO ADVERTISERS 



THE haff/crafh 

SX-146 AMATEUR BAND RECEIVER 



The Hoflicrafters SX-146 , , • Amateur Band Receiver 
of advanced design, employing a single conversion 
signal path and pre-mixed oscillator chain to assure 
high order frequency stability and freedom from 
adjacent channel cross-modulation products* Em- 
ploys a high frequency quartz crystal filter and 
has provision for the user installation of two 
more crystal filters. Tranceives with HT-46. 

SX-146 $269.95 

HA-19 100 Kc Crystal Calibrator $19.95 



ALSO IN STOCK: HT-46 Transmitter 



$349.95 



USED EQUIPMENT SPECIAL 

SX-111 $139.95 

SX-140 $59.95 

WRITE FOR LATEST COMPLETE LIST 



V4*t& 



P O BOX 312 



FONE 
603-?? 5^33 5 8 



CONCORD, N H 



Adirondack, 77 


Leeds, 74 


Aerotron (Ameco), 61 


Lewispaul, 88 


Alltronics. 88 


Liberty, 96 


Alvaradio. 76 




Amftron, 82 
Arcturus, 89 


Meshna, 40 


Arnold's, 93 
Arrow Sales, SI 


Midway, 92 
Military, 74 


ATV Research, 69 


Mostey, 15 


AS Magazine, 94 






Omega* 65, 82 


B C Electronics, 94 




Bigelow, 81 


Palo mar, 84 




Parks Laboratories, 52 


Ceco, 76 
Columbia, 93 


Poly Paks, 90 


Crabtree, 41 




Cushcraft, 79 


Quement. 39, 49 


Devices, 81 

DuPage FM, 75 


Radio Amateur Callback, 57 
Rohn, 5 


DX'er Magazine, 57 


Editors & Engineers, 78 


Salch, 93 


EpsUon Records, 94 


Scott, 76 


Estes Engineering, 77 


Sentry, 19 


Evans Radio. 96 


Slop, 83 




Sound History, 71 


Fair Radio, 92 


Swan, III 


Famerie, 77 




Freck Radio. 94 


TAB, 95 




Telrex, 23, 85 


Goodheart, 72 


Tower, 93 


Gotham, 95 


Trigger, 60 


Grantham School, 89 


Tristao, 57 




Tuck, 72 


H & L. 72 




Haf strom (BTI), 75 


UKW Magnzino. 82 


Hay dun. 63 


United Radio, 92 


HCJ Electronics, 77 


u s r Crystals, 81 


Henry Radio, 53, IV 




Hy-GaJn, 33 






Vanguard, 37, 79, 83, 84 


International Crystal, 3 


VHF Associates, 77 


James Research, 81 


Walkey, 88 


JAN Crystals, 88 


World Radio Labs, II 


Jefftronics, 89 


Westeom Engineering. 92 



« 

■ 
m 






• t 



• . 



•*^** 



% 
* 



i\ TOT^ 




'A 




i 



SSB-AM-CW 




i 



HOME STA TION-MOBILE-PORTABLE 



:t'w™ 



T, ■ " 



l\ y i 



\*- 



The new model 500C is the latest evolutionary develop- 
ment of a basic and well proven design philosophy. From 
the very beginning, with the introduction in 1961 of the 
first single band SSB Transceiver, Swan has followed a 
steady course of improvement by evolution. You might 
think that we would finally reach the point of leaving well 
enough alone, but with some 18 licensed hams in the 
engineering, sales and production departments of our 
organization, it just isn't possible. Thus, the new model 
5QDC, with greater power and additional features for even 
more operator enjoyment. 

RCA recently introduced a new heavy duty "blast rated" 
tetrode, the 6LQ6, With a pair of these rugged tubes the 
final amplifier operates with increased efficiency and 
power output on all bands. PEP input rating of the 500C is 
conservatively 520 Watts. Actually, an average pair of 
6LQ6's reach a peak input of over 570 Watts before flat- 
topping! 

Further refinement of the famous Swan VFO results in 
even greater mechanical and thermal stability and more 
precise dial calibration. Custom made planetary drives, ma- 
chined to extremely close tolerance, provide velvet smooth 
tuning. 

The 500C retains the same superior selectivity, of 
course, that we have been offering. The filter is made 
specially for us by C-F Networks, and it's no secret that it 
is a better filter than is being offered in any other trans- 
ceiver today. By moving the I.F. to 5500 KC, and increas- 
ing the number of tuned circuits in the receiver, we have 



achieved substantial improvement in image and spurious 
rejection. These improvements, coupled with additional 
TVI filtering, result in what we believe is the cleanest 
transceiver on the market 

For the CW operator the 500C includes a built-in side- 
tone monitor. Also, by installing the Swan Vox Accessory 
{model VX-2 ) you will have break-in CW operation. Thus. 
the model VX-2 now fulfills a dual function, both auto* 
matic voice control and break-in CW keying. Grid block 
keying of a pure CW carrier is employed with off set trans- 
mit frequency. 

The 500C embodies the Swan's well known dedication 
to craftsmanship, performance and reliability, with a serv- 
ice policy second to none. When you visit your Swan dealer 
and look over the 500C, we are sure that you will .-n n 
be glad we couldn't let well enough alone/ *j/U 

SWAN 350C Our improved standard model, now in produc- 
tion, and still only % \ $420 

ACCESSORIES 

MATCHING AC POWER SUPPLY 

12 VOLT DC POWER SUPPLY 

MODEL 410 FULL COVERAGE EXTERNAL VFO $95 

MODEL 22 DUAL VFO ADAPTOR $25 

MODEL 405X CRYSTAL CONTROLLED MARS OSCILLATOR $45 

MODEL VX-2 VOX and BREAK-IN CW UNIT $35 



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SEE IT AT YOUR 

SWAN DEALER 




ELECTRONICS 

Oceanside, California 



* SUBSIDfARy OF CUBIC CORP. 



WE EVEN SURPRISED OURSELVES 

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The 2K-2 was good ... in fact, it was the best linear amplifier for the amateur on the 
market. But now, thanks to a pair of new and improved Eimac 3-500Z tubes, pro- 
viding 1000 watts of plate dissipation, the 2K-3 operates with even greater power 
output and less drive. (Its so much better we're going to call it the 2K-3 now.) Still 
endowed with the same rugged and reliable mechanical construction, inspired de- 
sign and using only the very best components, the 2K-3 is unquestionably the finest. 
You have heard the strong clear signals of the 2K-2 by now. Why not go on the air 
with an even better signal? You can NOW with the new 2K-3. Console or desk model 
$745.00. Let us send you a descriptive brochure. 

6% FINANCE CHARGE • 10% DOWN OR TRADE-IN DOWN • NO FINANCE CHARGE IF 
PAID IN 90 DAYS • GOOD RECONDITIONED APPARATUS ' Nearly all makes & models. 
15 day trial. 90 day Warranty. 90 day trade back on NEW apparatus. Write for bulletin. 



TED HENRY (W6UOU) 



BOB HENRY (W0ARA) 



WALT HENRY (W6NRV) 




CALL DIRECT ... USE AREA CODE 



Butler, Missouri, 64730 

11240 W. Olympic, Los Angeles, Calif., 90064 

931 N. Euclid, Anaheim, Calif., 92801 



816 679-3127 
213 477-6701 
714 772-9200 



East Coast Rep.: Howard Laughrey, 2 Elizabeth St., 

Chappaqua. N.Y. 10514, (9141 CE 8 3683 



*. 



World's Largest Distributor of Amateur Radio Equipment'